From 9e1a2da2fcb2ae02ef0362f1d954b2e5e2f5547f Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?= Date: Tue, 22 Jul 2025 18:06:25 +0200 Subject: [PATCH 01/18] [setup] stop advertising Python 2 and 3.5 support --- setup.py | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) diff --git a/setup.py b/setup.py index 08b52e1e..26549c3e 100755 --- a/setup.py +++ b/setup.py @@ -138,12 +138,8 @@ def method_mod(name): 'bottle>=0.12.7, <0.13; python_version<"3.10"', 'bottle>=0.13, <0.14; python_version>="3.10"', 'waitress>=1.0', - 'configparser>=3.5.0, <5.0; python_version<"3"', - 'monotonic>=1.0; python_version<"3"', - 'selectors2>=2.0; python_version<"3"', - 'pathlib>=1.0; python_version<"3"', ], - python_requires=">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, <4", + python_requires=">=3.6, <4", ext_modules=[dsutilmodule, dataset_typemodule, csvimportmodule], @@ -171,7 +167,6 @@ def method_mod(name): "Operating System :: POSIX", "Operating System :: POSIX :: BSD :: FreeBSD", "Operating System :: POSIX :: Linux", - "Programming Language :: Python :: 2", "Programming Language :: Python :: 3", "Programming Language :: Python :: Implementation :: CPython", "Programming Language :: C", From 1faf9c19fa44182cb06465601a043d8d1c7c2cd0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?= Date: Tue, 22 Jul 2025 18:04:22 +0200 Subject: [PATCH 02/18] [test_methods] drop support for Python 2 --- .../a_test_csvexport_all_coltypes.py | 15 ++--- .../test_methods/a_test_csvexport_quoting.py | 6 +- .../a_test_csvimport_corner_cases.py | 11 ++-- .../test_methods/a_test_dataset_checksum.py | 27 ++++---- .../test_methods/a_test_dataset_concat.py | 3 - .../a_test_dataset_type_corner_cases.py | 25 ++++---- .../a_test_dataset_type_hashing.py | 14 ++-- accelerator/test_methods/a_test_json.py | 16 ++--- accelerator/test_methods/a_test_optionenum.py | 7 +- .../a_test_register_file_manual.py | 8 +-- accelerator/test_methods/a_test_shell_grep.py | 64 ++++++++----------- 11 files changed, 72 insertions(+), 124 deletions(-) diff --git a/accelerator/test_methods/a_test_csvexport_all_coltypes.py b/accelerator/test_methods/a_test_csvexport_all_coltypes.py index 9cb53081..0482b5d8 100644 --- a/accelerator/test_methods/a_test_csvexport_all_coltypes.py +++ b/accelerator/test_methods/a_test_csvexport_all_coltypes.py @@ -29,7 +29,6 @@ from accelerator import subjobs, status from accelerator.dsutil import _convfuncs -from accelerator.compat import PY2 def synthesis(job): dw = job.datasetwriter() @@ -54,11 +53,7 @@ def synthesis(job): check = {n for n in _convfuncs if not n.startswith('parsed:')} assert todo == check, 'Missing/extra column types: %r %r' % (check - todo, todo - check,) for name in sorted(todo): - if PY2 and name == 'pickle': - # pickle columns are not supported on python 2. - t = 'ascii' - else: - t = name + t = name dw.add(name, t, none_support=True) write = dw.get_split_write() write( @@ -67,7 +62,7 @@ def synthesis(job): date(2020, 6, 23), datetime(2020, 6, 23, 12, 13, 14), 1.0, float('-inf'), -10, -20, {'json': True}, 0xfedcba9876543210beef, - '...' if PY2 else 1+2j, time(12, 13, 14), 'bl\xe5', + 1+2j, time(12, 13, 14), 'bl\xe5', ) d = {} d['recursion'] = d @@ -77,7 +72,7 @@ def synthesis(job): date(1868, 1, 3), datetime(1868, 1, 3, 13, 14, 5), float('inf'), float('nan'), 0, 0, [False, None], 42.18, - '...' if PY2 else d, time(13, 14, 5), 'bl\xe4', + d, time(13, 14, 5), 'bl\xe4', ) write( None, None, None, @@ -145,7 +140,7 @@ def expect(*a): '2020-06-23', '2020-06-23 12:13:14', '1.0', '-inf', '-10', '-20', '{"json": true}', '1203552815971897489538799', - '...' if PY2 else '(1+2j)', '12:13:14', 'bl\xe5', + '(1+2j)', '12:13:14', 'bl\xe5', ) expect( 'b', 'False', 'bye', @@ -153,6 +148,6 @@ def expect(*a): '1868-01-03', '1868-01-03 13:14:05', 'inf', 'nan', '0', '0', '[false, null]', '42.18', - '...' if PY2 else "{'recursion': {...}}", '13:14:05', 'bl\xe4', + "{'recursion': {...}}", '13:14:05', 'bl\xe4', ) expect(*last_line) diff --git a/accelerator/test_methods/a_test_csvexport_quoting.py b/accelerator/test_methods/a_test_csvexport_quoting.py index 967903be..7fd550c8 100644 --- a/accelerator/test_methods/a_test_csvexport_quoting.py +++ b/accelerator/test_methods/a_test_csvexport_quoting.py @@ -23,15 +23,13 @@ ''' from accelerator import subjobs -from accelerator.compat import PY3 def test(job, prefix, none_support): expect = [[], [], []] def write(sliceno, a, b, c): w(a, b, c) if isinstance(c, bytes): - if PY3: - c = c.decode('utf-8', 'backslashreplace') + c = c.decode('utf-8', 'backslashreplace') else: c = repr(c) expect[sliceno].append((str(a), repr(b), c,)) @@ -76,7 +74,7 @@ def verify(source, lazy_quotes, q, sep, expect, **kw): separator=sep, **kw ) - with j.open('result.csv', 'r' if PY3 else 'rb') as fh: + with j.open('result.csv', 'r') as fh: got = fh.read() if lazy_quotes and sep: quote_func = make_lazy(sep, q) diff --git a/accelerator/test_methods/a_test_csvimport_corner_cases.py b/accelerator/test_methods/a_test_csvimport_corner_cases.py index f949055f..b483004a 100644 --- a/accelerator/test_methods/a_test_csvimport_corner_cases.py +++ b/accelerator/test_methods/a_test_csvimport_corner_cases.py @@ -31,10 +31,10 @@ from accelerator import subjobs from accelerator.dispatch import JobError from accelerator.dataset import Dataset -from accelerator.compat import PY3, uni +from accelerator.compat import uni def openx(filename): - return open(filename, "xb" if PY3 else "wbx") + return open(filename, "xb") def check_array(job, lines, filename, bad_lines=(), **options): d = {} @@ -124,11 +124,8 @@ def check_bad_file(job, name, data): ) require_failure(name, options) -if PY3: - def bytechr(i): - return chr(i).encode("iso-8859-1") -else: - bytechr = chr +def bytechr(i): + return chr(i).encode("iso-8859-1") def byteline(start, stop, nl, q): s = b''.join(bytechr(i) for i in range(start, stop) if i != nl) diff --git a/accelerator/test_methods/a_test_dataset_checksum.py b/accelerator/test_methods/a_test_dataset_checksum.py index 83d5a18b..5002ce9c 100644 --- a/accelerator/test_methods/a_test_dataset_checksum.py +++ b/accelerator/test_methods/a_test_dataset_checksum.py @@ -28,7 +28,6 @@ from accelerator.dataset import DatasetWriter from accelerator import subjobs from accelerator import blob -from accelerator.compat import PY3 test_data = [ ("a", b"A", b"0", 0.42, 18, [1, 2, 3], u"a", u"A"), @@ -48,12 +47,11 @@ def prepare(): unicode="unicode", unicode_none=("unicode", True), ) - if PY3: - # z so it sorts last - columns['zpickle'] = 'pickle' - for ix, v in enumerate(test_data): - test_data[ix] = v + ([ix, 'line %d' % (ix,), {'line': ix}, 42],) - test_data[-1][-1][-1] = float('-inf') + # z so it sorts last + columns['zpickle'] = 'pickle' + for ix, v in enumerate(test_data): + test_data[ix] = v + ([ix, 'line %d' % (ix,), {'line': ix}, 42],) + test_data[-1][-1][-1] = float('-inf') a = DatasetWriter(name="a", columns=columns) b = DatasetWriter(name="b", columns=columns, previous=a) c = DatasetWriter(name="c", columns=columns) @@ -99,11 +97,10 @@ def synthesis(prepare_res): a_uns_sum = ck(a, sort=False) b_uns_sum = ck(b, sort=False) assert a_uns_sum != b_uns_sum # they are not the same order - if PY3: - # Check that the pickle column really was included and works. - a_p_sum = ck(a, columns={'zpickle'}) - b_p_sum = ck(b, columns={'zpickle'}) - assert a_p_sum == b_p_sum # same values - a_uns_p_sum = ck(a, columns={'zpickle'}, sort=False) - b_uns_p_sum = ck(b, columns={'zpickle'}, sort=False) - assert a_uns_p_sum != b_uns_p_sum # but they are not the same order + # Check that the pickle column really was included and works. + a_p_sum = ck(a, columns={'zpickle'}) + b_p_sum = ck(b, columns={'zpickle'}) + assert a_p_sum == b_p_sum # same values + a_uns_p_sum = ck(a, columns={'zpickle'}, sort=False) + b_uns_p_sum = ck(b, columns={'zpickle'}, sort=False) + assert a_uns_p_sum != b_uns_p_sum # but they are not the same order diff --git a/accelerator/test_methods/a_test_dataset_concat.py b/accelerator/test_methods/a_test_dataset_concat.py index a04f84a0..4756117b 100644 --- a/accelerator/test_methods/a_test_dataset_concat.py +++ b/accelerator/test_methods/a_test_dataset_concat.py @@ -25,7 +25,6 @@ from itertools import chain from accelerator import subjobs, JobError -from accelerator.compat import PY2 from accelerator.dsutil import _type2iter def synthesis(job): @@ -50,8 +49,6 @@ def synthesis(job): } missing = set(_type2iter) - set(types.values()) assert not missing, missing - if PY2: - del types['n'] # no pickle type on python2 def data(ix): d = { diff --git a/accelerator/test_methods/a_test_dataset_type_corner_cases.py b/accelerator/test_methods/a_test_dataset_type_corner_cases.py index d9cab8e9..44d5ace0 100644 --- a/accelerator/test_methods/a_test_dataset_type_corner_cases.py +++ b/accelerator/test_methods/a_test_dataset_type_corner_cases.py @@ -37,7 +37,7 @@ from accelerator.dispatch import JobError from accelerator.dataset import Dataset, DatasetWriter from accelerator.dsutil import typed_writer -from accelerator.compat import PY3, UTC +from accelerator.compat import UTC from accelerator.standard_methods import dataset_type from accelerator import g @@ -137,14 +137,13 @@ def test_numbers(): values = [v + b'garbage' for v in values] verify('base %d i' % (base,), types, values, [27, 27, 27], all_source_types=all_source_types) all_source_types = False - # python2 has both int and long, let's not check exact types there. - verify('inty numbers', ['number', 'number:int'], [b'42', b'42.0', b'42.0000000', b'43.', b'.0'], [42, 42, 42, 43, 0], exact_types=PY3) + verify('inty numbers', ['number', 'number:int'], [b'42', b'42.0', b'42.0000000', b'43.', b'.0'], [42, 42, 42, 43, 0], exact_types=True) if options.numeric_comma: - verify('inty numbers numeric_comma', ['number', 'number:int'], [b'42', b'42,0', b'42,0000000', b'43,', b',0'], [42, 42, 42, 43, 0], numeric_comma=True, exact_types=PY3) + verify('inty numbers numeric_comma', ['number', 'number:int'], [b'42', b'42,0', b'42,0000000', b'43,', b',0'], [42, 42, 42, 43, 0], numeric_comma=True, exact_types=True) - # Python 2 accepts 42L as an integer, python 3 doesn't. The number + # Python 3 does not accepts 42L as an integer. The number # type falls back to python parsing, verify this works properly. - verify('integer with L', ['number'], [b'42L'], [42], want_fail=PY3) + verify('integer with L', ['number'], [b'42L'], [42], want_fail=True) # tests both that values outside the range are rejected # and that None works as a default value. @@ -981,19 +980,17 @@ def test_filter_bad_across_types(): want_bad = [tuple(l[1:]) for l in data if not l[0]] dw = DatasetWriter(name="filter bad across types", columns=columns, allow_missing_slices=True) cols_to_check = ['int32_10', 'bytes', 'json', 'unicode:utf-8'] - if PY3: - # z so it sorts last. - dw.add('zpickle', 'pickle') - cols_to_check.append('zpickle') - for ix in range(len(data)): - data[ix].append({ix}) + # z so it sorts last. + dw.add('zpickle', 'pickle') + cols_to_check.append('zpickle') + for ix in range(len(data)): + data[ix].append({ix}) dw.set_slice(0) want = [] def add_want(ix): v = data[ix] want.append((int(v[3]), v[1], json.loads(v[4]), v[6].decode('utf-8'),)) - if PY3: - want[-1] = want[-1] + (v[7],) + want[-1] = want[-1] + (v[7],) for ix, v in enumerate(data): if v[0]: add_want(ix) diff --git a/accelerator/test_methods/a_test_dataset_type_hashing.py b/accelerator/test_methods/a_test_dataset_type_hashing.py index b951165e..b1243182 100644 --- a/accelerator/test_methods/a_test_dataset_type_hashing.py +++ b/accelerator/test_methods/a_test_dataset_type_hashing.py @@ -34,7 +34,7 @@ from itertools import cycle from datetime import date, time, datetime -from accelerator.compat import unicode, PY3 +from accelerator.compat import unicode from accelerator import subjobs from accelerator.extras import DotDict from accelerator.dsutil import typed_writer @@ -158,19 +158,17 @@ def synthesis(job, slices): 'time' : ('time', True), 'unicode' : ('unicode', True), }) - if PY3: - # name it with z so it's last during iteration. - dw.add('zpickle', 'pickle', none_support=True) + # name it with z so it's last during iteration. + dw.add('zpickle', 'pickle', none_support=True) write = dw.get_split_write() data = { '42': ('ascii string', True, b'bytes string', 1+2j, 2+3j, date(2019, 12, 11), datetime(2019, 12, 11, 20, 7, 21), 1.5, 0.00000001, 99, -11, {"a": "b"}, 1e100, time(20, 7, 21), 'unicode string'), None: ( None, None, None, None, None, None, None, None, None, None, None, None, None, None, None), '18': ('ASCII STRING', False, b'BYTES STRING', 3-4j, 4-5j, date(1868, 1, 3), datetime(1868, 1, 3, 13, 14, 5), 2.5, -0.0000001, 67, -99, [42, ".."], 5e100, time(13, 14, 5), 'UNICODE STRING'), } - if PY3: - data['42'] += ([date(1, 2, 3), 'foo'],) - data[None] += (None,) - data['18'] += ({1, 2, 'c', b'bar'},) + data['42'] += ([date(1, 2, 3), 'foo'],) + data[None] += (None,) + data['18'] += ({1, 2, 'c', b'bar'},) write('42', *data['42']) write(None, *data[None]) write('18', *data['18']) diff --git a/accelerator/test_methods/a_test_json.py b/accelerator/test_methods/a_test_json.py index 90854263..653ebda6 100644 --- a/accelerator/test_methods/a_test_json.py +++ b/accelerator/test_methods/a_test_json.py @@ -29,7 +29,6 @@ from itertools import permutations from accelerator.extras import json_save, json_load, json_encode -from accelerator.compat import PY2, PY3 def test(name, input, want_obj, want_bytes, **kw): json_save(input, name, **kw) @@ -41,8 +40,7 @@ def test(name, input, want_obj, want_bytes, **kw): as_bytes = json_encode(input, as_str=False, **kw) assert isinstance(as_str, str) and isinstance(as_bytes, bytes), "json_encode returns the wrong types: %s %s" % (type(as_str), type(as_bytes),) assert as_bytes == got_bytes_raw, "json_save doesn't save the same thing json_encode returns for " + name - if PY3: - as_str = as_str.encode("utf-8") + as_str = as_str.encode("utf-8") assert as_bytes == as_str, "json_encode doesn't return the same data for as_str=True and False" got_obj = json_load(name) assert want_obj == got_obj, "%s roundtrips wrong (wanted %r, got %r)" % (name, want_obj, got_obj) @@ -79,8 +77,6 @@ def synthesis(): ) unicode_want = u"bl\xe4" - if PY2: - unicode_want = unicode_want.encode("utf-8") test( "unicode.json", u"bl\xe4", @@ -93,7 +89,7 @@ def synthesis(): fh.write(b'"bl\xc3\xa4"') assert json_load("utf-8.json") == unicode_want - # This is supposed to work on PY2, but not PY3. + # This not supposed to work on PY3. try: test( "string encoding.json", @@ -101,13 +97,9 @@ def synthesis(): [b"\xc3\xa4", b"\xc3\xa4", [b"\xc3\xa4", {b"\xc3\xa4": b"\xc3\xa4",},],], b'["\\u00e4","\\u00e4",["\\u00e4",{"\\u00e4": "\\u00e4"}]]', ) - string_encoding_ok = True + assert False, "Bytes are not supposed to work in json_encode on PY3" except TypeError: - string_encoding_ok = False - if PY2: - assert string_encoding_ok, "Bytes are supposed to work in json_encode on PY2" - else: - assert not string_encoding_ok, "Bytes are not supposed to work in json_encode on PY3" + pass # 720 permutations might be a bit much, but at least it's unlikely to # miss ordering problems. diff --git a/accelerator/test_methods/a_test_optionenum.py b/accelerator/test_methods/a_test_optionenum.py index 28f900e3..c95d2d2e 100644 --- a/accelerator/test_methods/a_test_optionenum.py +++ b/accelerator/test_methods/a_test_optionenum.py @@ -27,7 +27,6 @@ ''' from accelerator.extras import OptionEnum -from accelerator.compat import PY2 from accelerator import subjobs from accelerator import blob @@ -77,11 +76,7 @@ def synthesis(): return dict(options) check(abcd="a", efgh="h") check(ijkl="j", efgh="e") - if PY2: - # Passing "ä" is fine on PY2 too, but we get UTF-8 byte strings back. - check(uni=b"\xc3\xa4") - else: - check(uni="ä") + check(uni="ä") check(ijkl=None, dict=dict(foo="j")) check(mnSTARop="p", qSTARrSTARst="qwe", ijkl="k") check(mnSTARop="nah", qSTARrSTARst="really good value\n") diff --git a/accelerator/test_methods/a_test_register_file_manual.py b/accelerator/test_methods/a_test_register_file_manual.py index 3140b19b..d41ed386 100644 --- a/accelerator/test_methods/a_test_register_file_manual.py +++ b/accelerator/test_methods/a_test_register_file_manual.py @@ -21,7 +21,6 @@ from __future__ import division from __future__ import unicode_literals -from accelerator.compat import PY2 import os description = r''' @@ -62,9 +61,4 @@ def synthesis(job): os.mkdir('subdir/deep') with open('subdir/deep/file.txt', 'w') as fh: fh.write('written in a subdir, then registered with job.register_files() without a pattern.') - if PY2: - # No recursive support in glob in python 2. - assert job.register_files() == set() - assert job.register_files('*/*/*') == {'subdir/deep/file.txt'} - else: - assert job.register_files() == {'subdir/deep/file.txt'} + assert job.register_files() == {'subdir/deep/file.txt'} diff --git a/accelerator/test_methods/a_test_shell_grep.py b/accelerator/test_methods/a_test_shell_grep.py index 00c1fe1d..58cf79e9 100644 --- a/accelerator/test_methods/a_test_shell_grep.py +++ b/accelerator/test_methods/a_test_shell_grep.py @@ -38,7 +38,7 @@ from itertools import cycle from functools import partial -from accelerator.compat import PY2, PY3, izip_longest +from accelerator.compat import izip_longest from accelerator.dsutil import _convfuncs def grep_text(args, want, sep='\t', encoding='utf-8', unordered=False, check_output=check_output): @@ -94,12 +94,8 @@ def grep_json(args, want): if want != got: raise Exception('%r gave wrong result on line %d:\nWant: %r\nGot: %r' % (cmd, lineno, want, got,)) -if PY2: - def mk_bytes(low, high): - return b''.join(chr(c) for c in range(low, high)) -else: - def mk_bytes(low, high): - return bytes(range(low, high)) +def mk_bytes(low, high): + return bytes(range(low, high)) # looks like 'bar' when matching but 'foo' when printing # intended to catch if objects are evaluated too many times @@ -253,22 +249,21 @@ def frame(framevalues, *a): ], sep='', check_output=check_output_pty, ) - if PY3: # no pickle type on PY2 - pickle = mk_ds('pickle', ['pickle'], [TricksyObject()], [''], [{'foo'}]) - grep_text(['', pickle], [['foo'], [''], ["{'foo'}"]]) - grep_text(['.', pickle], [['foo'], ["{'foo'}"]]) - grep_text(['bar', pickle], [['foo']]) - # using -g with the same columns as output is a NOP - grep_text(['-g', 'pickle', 'bar', pickle], [['foo']]) - # but using it with a different set of columns is not - pickle2 = mk_ds('pickle2', ['ascii'], ['a'], ['b'], ['c'], parent=pickle) - grep_text(['-g', 'pickle', 'bar', pickle2], [['a', 'bar']]) - # order doesn't matter for equality, so here we're back to double evaluation. - grep_text(['-g', 'pickle', '-g', 'ascii', 'bar', pickle2], [['a', 'foo']]) - bytespickle = mk_ds('bytespickle', ['pickle'], [b'\xf0'], [b'\t']) - # pickles are str()d, not special cased like bytes columns - grep_text(['-f', 'raw', 'xf0', bytespickle], [["b'\\xf0'"]]) - grep_json(['', bytespickle], [{'pickle': "b'\\xf0'"}, {'pickle': "b'\\t'"}]) + pickle = mk_ds('pickle', ['pickle'], [TricksyObject()], [''], [{'foo'}]) + grep_text(['', pickle], [['foo'], [''], ["{'foo'}"]]) + grep_text(['.', pickle], [['foo'], ["{'foo'}"]]) + grep_text(['bar', pickle], [['foo']]) + # using -g with the same columns as output is a NOP + grep_text(['-g', 'pickle', 'bar', pickle], [['foo']]) + # but using it with a different set of columns is not + pickle2 = mk_ds('pickle2', ['ascii'], ['a'], ['b'], ['c'], parent=pickle) + grep_text(['-g', 'pickle', 'bar', pickle2], [['a', 'bar']]) + # order doesn't matter for equality, so here we're back to double evaluation. + grep_text(['-g', 'pickle', '-g', 'ascii', 'bar', pickle2], [['a', 'foo']]) + bytespickle = mk_ds('bytespickle', ['pickle'], [b'\xf0'], [b'\t']) + # pickles are str()d, not special cased like bytes columns + grep_text(['-f', 'raw', 'xf0', bytespickle], [["b'\\xf0'"]]) + grep_json(['', bytespickle], [{'pickle': "b'\\xf0'"}, {'pickle': "b'\\t'"}]) # --only-matching, both the part (default) and columns (with -l) in both csv and json grep_text(['-o', '-c', '1', b], [['1', ''], ['11', '1'], ['1'], ['11']]) @@ -282,11 +277,8 @@ def frame(framevalues, *a): ['printable', mk_bytes(32, 128)], ['not ascii', mk_bytes(128, 256)], ) - if PY2: - encoded_not_ascii = raw_not_ascii = '\ufffd'.encode('utf-8') * 128 - else: - raw_not_ascii = mk_bytes(128, 256) - encoded_not_ascii = raw_not_ascii.decode('utf-8', 'surrogateescape').encode('utf-8', 'surrogatepass') + raw_not_ascii = mk_bytes(128, 256) + encoded_not_ascii = raw_not_ascii.decode('utf-8', 'surrogateescape').encode('utf-8', 'surrogatepass') grep_text( ['--format=raw', '', allbytes], [ @@ -309,9 +301,9 @@ def frame(framevalues, *a): sep=b'\t', ) grep_json(['', allbytes], [ - {'ascii': 'control chars', 'bytes': mk_bytes(0, 32).decode('utf-8', 'surrogateescape' if PY3 else 'replace')}, - {'ascii': 'printable', 'bytes': mk_bytes(32, 128).decode('utf-8', 'surrogateescape' if PY3 else 'replace')}, - {'ascii': 'not ascii', 'bytes': mk_bytes(128, 256).decode('utf-8', 'surrogateescape' if PY3 else 'replace')}, + {'ascii': 'control chars', 'bytes': mk_bytes(0, 32).decode('utf-8', 'surrogateescape')}, + {'ascii': 'printable', 'bytes': mk_bytes(32, 128).decode('utf-8', 'surrogateescape')}, + {'ascii': 'not ascii', 'bytes': mk_bytes(128, 256).decode('utf-8', 'surrogateescape')}, ]) # header printing should happen between datasets only when columns change, @@ -620,11 +612,9 @@ def frame(framevalues, *a): grep_text(['-g', 'json', 'foo', alltypes], []) grep_text(['-g', 'bytes', 'tet', alltypes, 'ascii', 'unicode'], [['foo', 'codepoints\x00\xe4']]) grep_text(['-g', 'bytes', '\\x00', alltypes, 'bool'], [['True']]) - if PY3: - # python2 doesn't really handle non-utf8 bytes - grep_text(['-g', 'bytes', '\\udcff', alltypes, 'bool'], [['True']]) - grep_text(['--format=raw', '-g', 'json', '-i', 'foo', alltypes], [[b'foo', b'True', b'\xff\x00octets' if PY3 else b'\xef\xbf\xbd\x00octets', b'(1+2j)', b'(1.5-0.5j)', b'2021-09-20', b'2021-09-20 01:02:03', b'0.125', b'1e+42', b"[1, 2, 3, {'FOO': 'BAR'}, None]" if PY3 else b"[1, 2, 3, {u'FOO': u'BAR'}, None]", b'-2', b'04:05:06', b'codepoints\x00\xc3\xa4']], sep=b'\t', encoding=None) - grep_json([':05:', alltypes, 'bool', 'time', 'unicode', 'bytes'], [{'bool': True, 'time': '04:05:06', 'unicode': 'codepoints\x00\xe4', 'bytes': '\udcff\x00octets' if PY3 else '\ufffd\x00octets'}]) + grep_text(['-g', 'bytes', '\\udcff', alltypes, 'bool'], [['True']]) + grep_text(['--format=raw', '-g', 'json', '-i', 'foo', alltypes], [[b'foo', b'True', b'\xff\x00octets', b'(1+2j)', b'(1.5-0.5j)', b'2021-09-20', b'2021-09-20 01:02:03', b'0.125', b'1e+42', b"[1, 2, 3, {'FOO': 'BAR'}, None]", b'-2', b'04:05:06', b'codepoints\x00\xc3\xa4']], sep=b'\t', encoding=None) + grep_json([':05:', alltypes, 'bool', 'time', 'unicode', 'bytes'], [{'bool': True, 'time': '04:05:06', 'unicode': 'codepoints\x00\xe4', 'bytes': '\udcff\x00octets'}]) columns = [ 'ascii', @@ -695,8 +685,6 @@ def json_fixup(line): {'dataset': d, 'sliceno': 1, 'lineno': 0, 'data': want_json[1]}, ]) all_types = {n for n in _convfuncs if not n.startswith('parsed:')} - if PY2: - all_types.remove('pickle') assert used_types == all_types, 'Missing/extra column types: %r %r' % (all_types - used_types, used_types - all_types,) # test the smart tab mode with various lengths From ec7fb2a739ac9d3014596a68f2d580474fa87005 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?= Date: Tue, 22 Jul 2025 17:38:58 +0200 Subject: [PATCH 03/18] [standard_methods] drop support for Python 2 --- accelerator/standard_methods/a_csvexport.py | 21 ++++++------------- .../standard_methods/a_dataset_checksum.py | 10 +++------ .../standard_methods/a_dataset_type.py | 15 ++++--------- 3 files changed, 13 insertions(+), 33 deletions(-) diff --git a/accelerator/standard_methods/a_csvexport.py b/accelerator/standard_methods/a_csvexport.py index 79d9ffeb..a2f90ea6 100644 --- a/accelerator/standard_methods/a_csvexport.py +++ b/accelerator/standard_methods/a_csvexport.py @@ -32,7 +32,7 @@ from itertools import chain import gzip -from accelerator.compat import PY3, PY2, izip, imap, long +from accelerator.compat import izip, imap, long from accelerator import status @@ -71,16 +71,10 @@ def wrapped_write(s): json=JSONEncoder(sort_keys=True, ensure_ascii=True, check_circular=False).encode, ) -if PY3: - enc = str - format['bytes'] = lambda s: s.decode('utf-8', errors='backslashreplace') - format['number'] = repr - format['unicode'] = None -else: - enc = lambda s: s.encode('utf-8') - format['bytes'] = None - format['number'] = lambda n: str(n) if isinstance(n, long) else repr(n) - format['unicode'] = lambda s: s.encode('utf-8') +enc = str +format['bytes'] = lambda s: s.decode('utf-8', errors='backslashreplace') +format['number'] = repr +format['unicode'] = None def csvexport(sliceno, filename, labelsonfirstline): d = datasets.source[0] @@ -100,10 +94,7 @@ def csvexport(sliceno, filename, labelsonfirstline): open_func = partial(gzip.open, compresslevel=options.compression) else: open_func = open - if PY2: - open_func = partial(open_func, mode='wb') - else: - open_func = partial(open_func, mode='xt', encoding='utf-8') + open_func = partial(open_func, mode='xt', encoding='utf-8') if options.none_as: if isinstance(options.none_as, dict): bad_none = set(options.none_as) - set(options.labels) diff --git a/accelerator/standard_methods/a_dataset_checksum.py b/accelerator/standard_methods/a_dataset_checksum.py index 27b0c75f..9cc3f304 100644 --- a/accelerator/standard_methods/a_dataset_checksum.py +++ b/accelerator/standard_methods/a_dataset_checksum.py @@ -43,7 +43,6 @@ from heapq import merge from accelerator.extras import DotDict -from accelerator.compat import PY2 options = dict( columns = set(), @@ -52,11 +51,8 @@ datasets = ('source',) -if PY2: - bytesrepr = repr -else: - def bytesrepr(v): - return repr(v).encode('utf-8') +def bytesrepr(v): + return repr(v).encode('utf-8') def bytesstr(v): return v.encode('utf-8') @@ -86,7 +82,7 @@ def prepare(): # Same with pickle, but worse (many picklable values will break this). for n in columns: col = datasets.source.columns[n] - if col.type == 'bytes' or (col.type == 'ascii' and PY2): + if col.type == 'bytes': # doesn't need any encoding, but might need None-handling. if col.none_support: translators[n] = self_none diff --git a/accelerator/standard_methods/a_dataset_type.py b/accelerator/standard_methods/a_dataset_type.py index bb81c33f..f9514f45 100644 --- a/accelerator/standard_methods/a_dataset_type.py +++ b/accelerator/standard_methods/a_dataset_type.py @@ -29,7 +29,7 @@ from shutil import copyfileobj from struct import Struct -from accelerator.compat import unicode, itervalues, PY2 +from accelerator.compat import unicode, itervalues from accelerator.extras import OptionEnum, DotDict, quote from accelerator.dsutil import typed_writer, typed_reader @@ -373,14 +373,9 @@ def __getitem__(self, key): def __setitem__(self, key, value): self._s.pack_into(self.inner, key * 2, value) def __iter__(self): - if PY2: - def it(): - for o in range(len(self.inner) // 2): - yield self[o] - else: - def it(): - for v, in self._s.iter_unpack(self.inner): - yield v + def it(): + for v, in self._s.iter_unpack(self.inner): + yield v return it() @@ -540,8 +535,6 @@ def one_column(vars, colname, coltype, out_fns, for_hasher=False): if options.filter_bad: badmap = mmap(vars.badmap_fd, vars.badmap_size) vars.map_fhs.append(badmap) - if PY2: - badmap = IntegerBytesWrapper(badmap) if vars.rehashing: slicemap = mmap(vars.slicemap_fd, vars.slicemap_size) vars.map_fhs.append(slicemap) From 50e3d8626f80fce6301ea9a549c4bceeb4fd79ba Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?= Date: Tue, 22 Jul 2025 17:38:35 +0200 Subject: [PATCH 04/18] [accelerator] drop support for Python 2 --- accelerator/build.py | 19 ++++--------------- accelerator/colourwrapper.py | 7 +------ accelerator/dataset.py | 4 +--- accelerator/dispatch.py | 9 ++++----- accelerator/dsutil.py | 17 ++++------------- accelerator/extras.py | 34 +++++++++------------------------- accelerator/job.py | 20 ++++++++------------ accelerator/metadata.py | 14 ++++---------- accelerator/methods.py | 3 --- accelerator/runner.py | 3 --- accelerator/setupfile.py | 6 ++---- accelerator/shell/grep.py | 6 +++--- accelerator/shell/lined.py | 9 ++------- accelerator/shell/parser.py | 9 ++++----- accelerator/unixhttp.py | 16 ++++------------ accelerator/urd.py | 8 ++------ accelerator/web.py | 22 +++++++--------------- 17 files changed, 59 insertions(+), 147 deletions(-) diff --git a/accelerator/build.py b/accelerator/build.py index 7d0d12b1..2e8387b4 100644 --- a/accelerator/build.py +++ b/accelerator/build.py @@ -38,7 +38,7 @@ from importlib import import_module from argparse import RawTextHelpFormatter -from accelerator.compat import unicode, str_types, PY3 +from accelerator.compat import unicode, str_types from accelerator.compat import urlencode from accelerator.compat import getarglist @@ -404,10 +404,6 @@ def as_dep(self): class EmptyUrdResponse(UrdResponse): # so you can do "if urd.latest('foo'):" and similar. - # python2 version - def __nonzero__(self): - return False - # python3 version def __bool__(self): return False @@ -468,10 +464,7 @@ def __init__(self, a, info, user, password, horizon=None, default_workdir=None): self.horizon = horizon self.default_workdir = default_workdir auth = '%s:%s' % (user, password,) - if PY3: - auth = b64encode(auth.encode('utf-8')).decode('ascii') - else: - auth = b64encode(auth) + auth = b64encode(auth.encode('utf-8')).decode('ascii') self._headers = {'Content-Type': 'application/json', 'Authorization': 'Basic ' + auth} self._auth_tested = False self._reset() @@ -709,12 +702,8 @@ def find_automata(a, script): module_ref = import_module(module_name) return module_ref except ImportError as e: - if PY3: - if not e.msg[:-1].endswith(script): - raise - else: - if not e.message.endswith(script): - raise + if not e.msg[:-1].endswith(script): + raise raise BuildError('No build script "%s" found in {%s}' % (script, ', '.join(package))) diff --git a/accelerator/colourwrapper.py b/accelerator/colourwrapper.py index 1fad2426..b7fddce7 100644 --- a/accelerator/colourwrapper.py +++ b/accelerator/colourwrapper.py @@ -24,7 +24,6 @@ import sys, os from functools import partial -from accelerator.compat import PY2 from accelerator.error import ColourError # all gray colours in the 256 colour palette in intensity order @@ -102,11 +101,7 @@ def __init__(self): self._on = {k: '\x1b[%sm' % (v,) for k, v in self._all.items()} self._on['RESET'] = '\x1b[m' self._all['RESET'] = '' - if PY2: - self._on = {k.encode('ascii'): v.encode('ascii') for k, v in self._on.items()} - self._off = dict.fromkeys(self._on, b'') - else: - self._off = dict.fromkeys(self._on, '') + self._off = dict.fromkeys(self._on, '') self.enable() self.__all__ = [k for k in dir(self) if not k.startswith('_')] self._lined = False diff --git a/accelerator/dataset.py b/accelerator/dataset.py index 0c2ee9ca..72c92918 100644 --- a/accelerator/dataset.py +++ b/accelerator/dataset.py @@ -34,7 +34,7 @@ from math import isnan import datetime -from accelerator.compat import unicode, uni, ifilter, imap, iteritems, PY2 +from accelerator.compat import unicode, uni, ifilter, imap, iteritems from accelerator.compat import builtins, open, getarglist, izip, izip_longest from accelerator.compat import str_types, int_types, FileNotFoundError @@ -1597,8 +1597,6 @@ def set_compressions(self, compressions): self._compressions = dict.fromkeys(self.columns, compressions) else: self._compressions.update(compressions) - if PY2: - self._compressions = {uni(k): uni(v) for k, v in self._compressions.items()} def finish(self): """Normally you don't need to call this, but if you want to diff --git a/accelerator/dispatch.py b/accelerator/dispatch.py index 0e812371..9defffd0 100644 --- a/accelerator/dispatch.py +++ b/accelerator/dispatch.py @@ -25,7 +25,7 @@ import os from signal import SIGTERM, SIGKILL -from accelerator.compat import PY3, monotonic +from accelerator.compat import monotonic from accelerator.statmsg import children, statmsg_endwait from accelerator.build import JobError @@ -70,10 +70,9 @@ def run(cmd, close_in_child, keep_in_child, no_stdin=True): devnull = os.open('/dev/null', os.O_RDONLY) os.dup2(devnull, 0) os.close(devnull) - if PY3: - keep_in_child.update([1, 2]) - for fd in keep_in_child: - os.set_inheritable(fd, True) + keep_in_child.update([1, 2]) + for fd in keep_in_child: + os.set_inheritable(fd, True) os.execv(cmd[0], cmd) os._exit() diff --git a/accelerator/dsutil.py b/accelerator/dsutil.py index ab38d004..615bd14f 100644 --- a/accelerator/dsutil.py +++ b/accelerator/dsutil.py @@ -22,7 +22,7 @@ from __future__ import division from accelerator import _dsutil -from accelerator.compat import str_types, PY3 +from accelerator.compat import str_types from accelerator.standard_methods._dataset_type import strptime, strptime_i _convfuncs = { @@ -84,12 +84,8 @@ class WriteJson(object): min = max = None def __init__(self, *a, **kw): default = kw.pop('default', _nodefault) - if PY3: - self.fh = _dsutil.WriteUnicode(*a, **kw) - self.encode = JSONEncoder(ensure_ascii=False, separators=(',', ':')).encode - else: - self.fh = _dsutil.WriteBytes(*a, **kw) - self.encode = JSONEncoder(ensure_ascii=True, separators=(',', ':')).encode + self.fh = _dsutil.WriteUnicode(*a, **kw) + self.encode = JSONEncoder(ensure_ascii=False, separators=(',', ':')).encode self.encode = self._wrap_encode(self.encode, default) def _wrap_encode(self, encode, default): if default is _nodefault: @@ -141,10 +137,7 @@ def wrapped_encode(o): class ReadJson(object): __slots__ = ('fh', 'decode') def __init__(self, *a, **kw): - if PY3: - self.fh = _dsutil.ReadUnicode(*a, **kw) - else: - self.fh = _dsutil.ReadBytes(*a, **kw) + self.fh = _dsutil.ReadUnicode(*a, **kw) self.decode = JSONDecoder().decode def __next__(self): return self.decode(next(self.fh)) @@ -167,7 +160,6 @@ class WritePickle(object): __slots__ = ('fh',) min = max = None def __init__(self, *a, **kw): - assert PY3, "Pickle columns require python 3, sorry" assert 'default' not in kw, "default not supported for Pickle, sorry" self.fh = _dsutil.WriteBytes(*a, **kw) def write(self, o): @@ -189,7 +181,6 @@ def __exit__(self, type, value, traceback): class ReadPickle(object): __slots__ = ('fh',) def __init__(self, *a, **kw): - assert PY3, "Pickle columns require python 3, sorry" self.fh = _dsutil.ReadBytes(*a, **kw) def __next__(self): return pickle_loads(next(self.fh)) diff --git a/accelerator/extras.py b/accelerator/extras.py index 6fd96121..526953d9 100644 --- a/accelerator/extras.py +++ b/accelerator/extras.py @@ -32,7 +32,7 @@ from functools import partial import sys -from accelerator.compat import PY2, PY3, pickle, izip, iteritems, first_value +from accelerator.compat import pickle, izip, iteritems, first_value from accelerator.compat import num_types, uni, unicode, str_types from accelerator.error import AcceleratorError @@ -212,10 +212,7 @@ def pickle_load(filename='result.pickle', jobid=None, sliceno=None, encoding='by filename = _fn(filename, jobid, sliceno) with status('Loading ' + filename): with open(filename, 'rb') as fh: - if PY3: - return pickle.load(fh, encoding=encoding) - else: - return pickle.load(fh) + return pickle.load(fh, encoding=encoding) def json_encode(variable, sort_keys=True, as_str=False): @@ -238,13 +235,11 @@ def typefix(e): return dict_type((typefix(k), typefix(v)) for k, v in iteritems(e)) elif isinstance(e, (list, tuple, set,)): return [typefix(v) for v in e] - elif PY2 and isinstance(e, bytes): - return uni(e) else: return e variable = typefix(variable) res = json.dumps(variable, indent=4, sort_keys=sort_keys) - if PY3 and not as_str: + if not as_str: res = res.encode('ascii') return res @@ -271,20 +266,16 @@ def _unicode_as_utf8bytes(obj): else: return obj -def json_decode(s, unicode_as_utf8bytes=PY2): +def json_decode(s, unicode_as_utf8bytes=False): if unicode_as_utf8bytes: return _unicode_as_utf8bytes(json.loads(s, object_pairs_hook=DotDict)) else: return json.loads(s, object_pairs_hook=DotDict) -def json_load(filename='result.json', jobid=None, sliceno=None, unicode_as_utf8bytes=PY2): +def json_load(filename='result.json', jobid=None, sliceno=None, unicode_as_utf8bytes=False): filename = _fn(filename, jobid, sliceno) - if PY3: - with open(filename, 'r', encoding='utf-8') as fh: - data = fh.read() - else: - with open(filename, 'rb') as fh: - data = fh.read() + with open(filename, 'r', encoding='utf-8') as fh: + data = fh.read() return json_decode(data, unicode_as_utf8bytes) @@ -292,9 +283,6 @@ def quote(s): """Quote s unless it looks fine without""" s = unicode(s) r = repr(s) - if PY2: - # remove leading u - r = r[1:] if s and len(s) + 2 == len(r) and not any(c.isspace() for c in s): return s else: @@ -346,8 +334,7 @@ def __init__(self, filename, temp=None, _hidden=False): def __enter__(self): self._status = status('Saving ' + self.filename) self._status.__enter__() - # stupid python3 feels that w and x are exclusive, while python2 requires both. - fh = getattr(self, '_open', open)(self.tmp_filename, 'xb' if PY3 else 'wbx') + fh = getattr(self, '_open', open)(self.tmp_filename, 'xb') self.close = fh.close return fh def __exit__(self, e_type, e_value, e_tb): @@ -548,8 +535,7 @@ def __repr__(self): class OptionEnumValue(str): - if PY3: # python2 doesn't support slots on str subclasses - __slots__ = ('_valid', '_prefixes') + __slots__ = ('_valid', '_prefixes') @staticmethod def _mktype(name, valid, prefixes): @@ -600,8 +586,6 @@ def __new__(cls, values, none_ok=False): if isinstance(values, str_types): values = values.replace(',', ' ').split() values = list(values) - if PY2: - values = [v.encode('utf-8') if isinstance(v, unicode) else v for v in values] valid = set(values) prefixes = [] for v in values: diff --git a/accelerator/job.py b/accelerator/job.py index d02c6621..ebe4df57 100644 --- a/accelerator/job.py +++ b/accelerator/job.py @@ -27,7 +27,7 @@ from functools import wraps from pathlib import Path -from accelerator.compat import unicode, PY2, PY3, open, iteritems, FileNotFoundError +from accelerator.compat import unicode, open, iteritems, FileNotFoundError from accelerator.error import NoSuchJobError, NoSuchWorkdirError, NoSuchDatasetError, AcceleratorError @@ -196,7 +196,7 @@ def load(self, filename='result.pickle', sliceno=None, encoding='bytes', default raise return default - def json_load(self, filename='result.json', sliceno=None, unicode_as_utf8bytes=PY2, default=_nodefault): + def json_load(self, filename='result.json', sliceno=None, unicode_as_utf8bytes=False, default=_nodefault): from accelerator.extras import json_load try: return json_load(self.filename(filename, sliceno), unicode_as_utf8bytes=unicode_as_utf8bytes) @@ -360,7 +360,7 @@ def open(self, filename, mode='r', sliceno=None, encoding=None, errors=None, tem return Job.open(self, filename, mode, sliceno, encoding, errors) if 'b' not in mode and encoding is None: encoding = 'utf-8' - if PY3 and 'x' not in mode: + if 'x' not in mode: mode = mode.replace('w', 'x') def _open(fn, _mode): # ignore the passed mode, use the one we have @@ -380,11 +380,11 @@ def register_file(self, filename): from accelerator.extras import saved_files saved_files[filename] = 0 - def register_files(self, pattern='**/*' if PY3 else '*'): + def register_files(self, pattern='**/*'): """Bulk register files matching a pattern. Tries to exclude internal files automatically. Does not register temp-files. - The default pattern registers everything (recursively, unless python 2). + The default pattern registers everything, recursively. Returns which files were registered. """ from accelerator.extras import saved_files @@ -394,11 +394,7 @@ def register_files(self, pattern='**/*' if PY3 else '*'): assert not pattern.startswith('../') forbidden = ('setup.json', 'post.json', 'method.tar.gz', 'link_result.pickle') res = set() - if PY3: - files = iglob(pattern, recursive=True) - else: - # No recursive support on python 2. - files = iglob(pattern) + files = iglob(pattern, recursive=True) for fn in files: if ( fn in forbidden or @@ -464,7 +460,7 @@ def load(self, filename=None, sliceno=None, encoding='bytes', default=_nodefault raise NoSuchJobError('Can not load named / sliced file on ') return None - def json_load(self, filename=None, sliceno=None, unicode_as_utf8bytes=PY2, default=_nodefault): + def json_load(self, filename=None, sliceno=None, unicode_as_utf8bytes=False, default=_nodefault): return self.load(filename, sliceno, default=default) @property # so it can return the same instance as all other NoJob things @@ -500,7 +496,7 @@ def load(self, sliceno=None, encoding='bytes', default=_nodefault): raise return default - def json_load(self, sliceno=None, unicode_as_utf8bytes=PY2, default=_nodefault): + def json_load(self, sliceno=None, unicode_as_utf8bytes=False, default=_nodefault): from accelerator.extras import json_load try: return json_load(self.filename(sliceno), unicode_as_utf8bytes=unicode_as_utf8bytes) diff --git a/accelerator/metadata.py b/accelerator/metadata.py index 3691d8fd..5f2af074 100644 --- a/accelerator/metadata.py +++ b/accelerator/metadata.py @@ -30,14 +30,10 @@ import traceback import zlib -from accelerator.compat import PY3, FileNotFoundError +from accelerator.compat import FileNotFoundError from accelerator.extras import json_decode -if PY3: - crc32 = zlib.crc32 -else: - def crc32(data): - return zlib.crc32(data) & 0xffffffff +crc32 = zlib.crc32 def b64hash_setup(filename): @@ -60,9 +56,7 @@ def job_metadata(job): 'setup_hash': b64hash_setup(job.filename('setup.json')), 'host': socket.gethostname(), } - res = json.dumps(d) - if PY3: - res = res.encode('ascii') + res = json.dumps(d).encode('ascii') return res @@ -164,7 +158,7 @@ def chunks(data): def extract_gif(fh): def unchunk(pos): while pos + 1 < len(data): - z, = struct.unpack('= 400: @@ -108,9 +102,7 @@ def call(url, data=None, fmt=json_decode, headers={}, server_name='server', retr pass except HTTPError as e: if resp is None and e.fp: - resp = e.fp.read() - if PY3: - resp = resp.decode('utf-8') + resp = e.fp.read().decode('utf-8') msg = '%s says %d: %s' % (server_name, e.code, resp,) if server_name == 'urd' and 400 <= e.code < 500: if e.code == 401: diff --git a/accelerator/urd.py b/accelerator/urd.py index f57e36b7..11cc393b 100644 --- a/accelerator/urd.py +++ b/accelerator/urd.py @@ -39,7 +39,6 @@ import signal from accelerator.compat import iteritems, itervalues, unicode -from accelerator.compat import PY3 from accelerator.colourwrapper import colour from accelerator.shell.parser import ArgumentParser from accelerator.unixhttp import WaitressServer @@ -73,8 +72,7 @@ class TimeStamp(str): Extra parts sort after. """ - if PY3: # python2 doesn't support slots on str subclasses - __slots__ = ('_parts') + __slots__ = ('_parts') def __new__(cls, ts): if isinstance(ts, TimeStamp): @@ -512,9 +510,7 @@ def cmpfunc(k, ts): @route('/add', method='POST') @auth_basic(auth) def add(): - body = request.body - if PY3: - body = TextIOWrapper(body, encoding='utf-8') + body = TextIOWrapper(request.body, encoding='utf-8') data = Entry(json.load(body)) if data.user != request.auth[0]: abort(401, "Error: user does not match authentication!") diff --git a/accelerator/web.py b/accelerator/web.py index d3871ff4..ffa1bf08 100644 --- a/accelerator/web.py +++ b/accelerator/web.py @@ -18,19 +18,12 @@ # # ############################################################################ -from accelerator.compat import PY3, unicode - -if PY3: - from socketserver import ThreadingMixIn - from http.server import HTTPServer, BaseHTTPRequestHandler - from socketserver import UnixStreamServer - from urllib.parse import parse_qs, unquote_plus -else: - from SocketServer import ThreadingMixIn - from BaseHTTPServer import HTTPServer, BaseHTTPRequestHandler - from SocketServer import UnixStreamServer - from urlparse import parse_qs - from urllib import unquote_plus +from accelerator.compat import unicode + +from socketserver import ThreadingMixIn +from http.server import HTTPServer, BaseHTTPRequestHandler +from socketserver import UnixStreamServer +from urllib.parse import parse_qs, unquote_plus class ThreadedHTTPServer(ThreadingMixIn, HTTPServer): request_queue_size = 512 @@ -76,8 +69,7 @@ def do_POST(self): bare_ctype = ctype.split(";", 1)[0].strip() if bare_ctype == "application/x-www-form-urlencoded": cgi_args = parse_qs(data, keep_blank_values=True) - if PY3: - cgi_args = {k.decode('ascii'): v for k, v in cgi_args.items()} + cgi_args = {k.decode('ascii'): v for k, v in cgi_args.items()} else: cgi_args = {None: [data]} self.is_head = False From 9d6b48bb12e44431d62f5d4d0bcb12ac0054228b Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?= Date: Tue, 22 Jul 2025 18:06:11 +0200 Subject: [PATCH 05/18] [compat] drop support for Python 2 --- accelerator/compat.py | 162 +++++++++--------------------------------- accelerator/extras.py | 2 +- 2 files changed, 36 insertions(+), 128 deletions(-) diff --git a/accelerator/compat.py b/accelerator/compat.py index ce8a6a89..da324b09 100644 --- a/accelerator/compat.py +++ b/accelerator/compat.py @@ -33,131 +33,41 @@ except ImportError: def _setproctitle(title): pass -if sys.version_info[0] == 2: - PY2 = True - PY3 = False - import __builtin__ as builtins - import cPickle as pickle - FileNotFoundError = (builtins.OSError, builtins.IOError) - PermissionError = builtins.IOError - from urllib import quote as url_quote, quote_plus, unquote_plus, urlencode - from urllib2 import urlopen, Request, URLError, HTTPError - from itertools import izip, izip_longest, imap, ifilter - from Queue import Queue, Full as QueueFull, Empty as QueueEmpty - import selectors2 as selectors - try: - from monotonic import monotonic - except ImportError: - from time import time as monotonic - from types import NoneType - str_types = (str, unicode,) - int_types = (int, long,) - num_types = (int, float, long,) - unicode = builtins.unicode - long = builtins.long - def iterkeys(d): - return d.iterkeys() - def itervalues(d): - return d.itervalues() - def iteritems(d): - return d.iteritems() - from io import open - def getarglist(func): - from inspect import getargspec - return getargspec(func).args - def terminal_size(): - from termios import TIOCGWINSZ - import struct - from fcntl import ioctl - from collections import namedtuple - from os import environ - def ifgood(name): - try: - v = int(environ[name]) - if v > 0: - return v - except (KeyError, ValueError): - pass - lines, columns = ifgood('LINES'), ifgood('COLUMNS') - if not lines or not columns: - try: - fb_lines, fb_columns, _, _ = struct.unpack('HHHH', ioctl(0, TIOCGWINSZ, struct.pack('HHHH', 0, 0, 0, 0))) - except Exception: - fb_lines, fb_columns = 24, 80 - return namedtuple('terminal_size', 'columns lines')(columns or fb_columns, lines or fb_lines) - def shell_quote(v): - ok = set('abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789,.:/+-_') - if any(c not in ok for c in v): - return "'%s'" % (v.replace("'", "'\"'\"'"),) - else: - return v or "''" - import datetime - _timedelta_0 = datetime.timedelta(0) - class timezone(datetime.tzinfo): - __slots__ = () - def __new__(cls, offset, name=None): - if UTC is None: # when constructing the singleton - return datetime.tzinfo.__new__(cls) - if name is not None or offset != _timedelta_0: - raise ValueError("This python 2 compat class only supports UTC.") - return UTC - def dst(self, dt): - return _timedelta_0 - def utcoffset(self, dt): - return _timedelta_0 - def tzname(self, dt): - return b'UTC' - def __reduce__(self): - return _utc_pickle - def __repr__(self): - return b'accelerator.compat.UTC' - def __str__(self): - return b'UTC' - UTC = None - UTC = timezone(None) - timezone.__module__ = b'datetime' # so it pickles the way we want - datetime.timezone = timezone - _utc_pickle = (timezone, (_timedelta_0,)) # same thing the python 3 version pickles as - del timezone - del datetime -else: - PY2 = False - PY3 = True - import builtins - FileNotFoundError = builtins.FileNotFoundError - PermissionError = builtins.PermissionError - import pickle - from urllib.parse import quote as url_quote, quote_plus, unquote_plus, urlencode - from urllib.request import urlopen, Request - from urllib.error import URLError, HTTPError - izip = zip - from itertools import zip_longest as izip_longest - imap = map - ifilter = filter - from queue import Queue, Full as QueueFull, Empty as QueueEmpty - import selectors - from time import monotonic - NoneType = type(None) - str_types = (str,) - int_types = (int,) - num_types = (int, float,) - unicode = str - open = builtins.open - long = int - def iterkeys(d): - return iter(d.keys()) - def itervalues(d): - return iter(d.values()) - def iteritems(d): - return iter(d.items()) - def getarglist(func): - from inspect import getfullargspec - return getfullargspec(func).args - from shutil import get_terminal_size as terminal_size - from shlex import quote as shell_quote - import datetime - UTC = datetime.timezone.utc - del datetime +import builtins +FileNotFoundError = builtins.FileNotFoundError +PermissionError = builtins.PermissionError +import pickle +from urllib.parse import quote as url_quote, quote_plus, unquote_plus, urlencode +from urllib.request import urlopen, Request +from urllib.error import URLError, HTTPError +izip = zip +from itertools import zip_longest as izip_longest +imap = map +ifilter = filter +from queue import Queue, Full as QueueFull, Empty as QueueEmpty +import selectors +from time import monotonic +NoneType = type(None) +str_types = (str,) +int_types = (int,) +num_types = (int, float,) +unicode = str +open = builtins.open +long = int +def iterkeys(d): + return iter(d.keys()) +def itervalues(d): + return iter(d.values()) +def iteritems(d): + return iter(d.items()) +def getarglist(func): + from inspect import getfullargspec + return getfullargspec(func).args +from shutil import get_terminal_size as terminal_size +from shlex import quote as shell_quote +import datetime +UTC = datetime.timezone.utc +del datetime def first_value(d): return next(itervalues(d) if isinstance(d, dict) else iter(d)) @@ -194,6 +104,4 @@ def setproctitle(title): title = '%s %s' % (g.job, uni(title),) else: title = uni(title) - if PY2: - title = title.encode('utf-8') _setproctitle(title) diff --git a/accelerator/extras.py b/accelerator/extras.py index 526953d9..75fd3a42 100644 --- a/accelerator/extras.py +++ b/accelerator/extras.py @@ -33,7 +33,7 @@ import sys from accelerator.compat import pickle, izip, iteritems, first_value -from accelerator.compat import num_types, uni, unicode, str_types +from accelerator.compat import num_types, unicode, str_types from accelerator.error import AcceleratorError from accelerator.job import Job, JobWithFile From 1b853d7bbd121a6bcddf5aaa163124a9ab00f120 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?= Date: Thu, 24 Jul 2025 11:11:31 +0200 Subject: [PATCH 06/18] [compat] drop support for Python < 3.6 --- accelerator/compat.py | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/accelerator/compat.py b/accelerator/compat.py index da324b09..37e6cabe 100644 --- a/accelerator/compat.py +++ b/accelerator/compat.py @@ -85,14 +85,11 @@ def uni(s): def url_quote_more(s): return quote_plus(s).replace('+', '%20') -if sys.version_info < (3, 6): - fmt_num = '{:n}'.format -else: - def fmt_num(num): - if isinstance(num, float): - return '{:_.6g}'.format(num) - else: - return '{:_}'.format(num) +def fmt_num(num): + if isinstance(num, float): + return '{:_.6g}'.format(num) + else: + return '{:_}'.format(num) # This is used in the method launcher to set different titles for each # phase/slice. You can use it in the method to override that if you want. From 7bb293406858cf7894c43d6224f71c263d6de8e2 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?= Date: Thu, 24 Jul 2025 11:25:44 +0200 Subject: [PATCH 07/18] [accelerator] drop usage of compat.long This is legacy from when Python (<2) was dumber. There's no need to keep that now. And everywhere where long was being used "int" was also used, making it completely pointless. The definition in compat is kept for backwards compatibility. --- accelerator/methods.py | 6 +++--- accelerator/setupfile.py | 4 ++-- accelerator/standard_methods/a_csvexport.py | 2 +- 3 files changed, 6 insertions(+), 6 deletions(-) diff --git a/accelerator/methods.py b/accelerator/methods.py index c4dbdb8d..ca7afd0e 100644 --- a/accelerator/methods.py +++ b/accelerator/methods.py @@ -32,7 +32,7 @@ from importlib import import_module from accelerator.compat import iteritems, itervalues, first_value -from accelerator.compat import NoneType, unicode, long, monotonic +from accelerator.compat import NoneType, unicode, monotonic from accelerator.colourwrapper import colour from accelerator.error import AcceleratorError @@ -145,7 +145,7 @@ def params2optset(self, params): def _reprify(o): if isinstance(o, OptionDefault): o = o.default - if isinstance(o, (bytes, str, int, float, long, bool, NoneType)): + if isinstance(o, (bytes, str, int, float, bool, NoneType)): return repr(o) if isinstance(o, set): return '[%s]' % (', '.join(map(_reprify, _sorted_set(o))),) @@ -186,7 +186,7 @@ def fixup(item): return type(item)(l) if isinstance(item, (type, OptionEnum)): return None - assert isinstance(item, (bytes, unicode, int, float, long, bool, OptionEnum, NoneType, datetime.datetime, datetime.date, datetime.time, datetime.timedelta, pathlib.PosixPath, pathlib.PurePosixPath,)), type(item) + assert isinstance(item, (bytes, unicode, int, float, bool, OptionEnum, NoneType, datetime.datetime, datetime.date, datetime.time, datetime.timedelta, pathlib.PosixPath, pathlib.PurePosixPath,)), type(item) return item def fixup0(item): if isinstance(item, RequiredOption): diff --git a/accelerator/setupfile.py b/accelerator/setupfile.py index 8e5c3e59..ce0ed0b6 100644 --- a/accelerator/setupfile.py +++ b/accelerator/setupfile.py @@ -28,7 +28,7 @@ from datetime import datetime, date, time, timedelta from pathlib import PosixPath, PurePosixPath -from accelerator.compat import iteritems, unicode, long, uni +from accelerator.compat import iteritems, unicode, uni from accelerator.error import AcceleratorError, NoSuchJobError from accelerator.extras import DotDict, json_load, json_save, json_encode @@ -130,7 +130,7 @@ def copy_json_safe(src): elif isinstance(src, timedelta): return src.total_seconds() else: - assert isinstance(src, (str, unicode, int, float, long, bool)) or src is None, "%s not supported in data" % (type(src),) + assert isinstance(src, (str, unicode, int, float, bool)) or src is None, "%s not supported in data" % (type(src),) return src def encode_setup(data, sort_keys=True, as_str=False): diff --git a/accelerator/standard_methods/a_csvexport.py b/accelerator/standard_methods/a_csvexport.py index a2f90ea6..8ef54f1e 100644 --- a/accelerator/standard_methods/a_csvexport.py +++ b/accelerator/standard_methods/a_csvexport.py @@ -32,7 +32,7 @@ from itertools import chain import gzip -from accelerator.compat import izip, imap, long +from accelerator.compat import izip, imap from accelerator import status From 24a1e809aa5b2c7da5a0a35d58a1bc4c029aad30 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?= Date: Thu, 24 Jul 2025 13:53:30 +0200 Subject: [PATCH 08/18] [accelerator] drop usage of compat.open This is legacy from when in Python 2 builtins.open was different to io.open. Python 3 open is right straight away, so there is no need to importing it from compat. --- accelerator/configfile.py | 2 +- accelerator/dataset.py | 2 +- accelerator/job.py | 2 +- accelerator/shell/__init__.py | 1 - accelerator/test_methods/a_test_urd.py | 2 +- 5 files changed, 4 insertions(+), 5 deletions(-) diff --git a/accelerator/configfile.py b/accelerator/configfile.py index 555c41af..b364e1fa 100644 --- a/accelerator/configfile.py +++ b/accelerator/configfile.py @@ -26,7 +26,7 @@ import os import shlex -from accelerator.compat import url_quote_more, open +from accelerator.compat import url_quote_more from accelerator.extras import DotDict diff --git a/accelerator/dataset.py b/accelerator/dataset.py index 72c92918..436e1eb7 100644 --- a/accelerator/dataset.py +++ b/accelerator/dataset.py @@ -35,7 +35,7 @@ import datetime from accelerator.compat import unicode, uni, ifilter, imap, iteritems -from accelerator.compat import builtins, open, getarglist, izip, izip_longest +from accelerator.compat import builtins, getarglist, izip, izip_longest from accelerator.compat import str_types, int_types, FileNotFoundError from accelerator import blob diff --git a/accelerator/job.py b/accelerator/job.py index ebe4df57..31a92787 100644 --- a/accelerator/job.py +++ b/accelerator/job.py @@ -27,7 +27,7 @@ from functools import wraps from pathlib import Path -from accelerator.compat import unicode, open, iteritems, FileNotFoundError +from accelerator.compat import unicode, iteritems, FileNotFoundError from accelerator.error import NoSuchJobError, NoSuchWorkdirError, NoSuchDatasetError, AcceleratorError diff --git a/accelerator/shell/__init__.py b/accelerator/shell/__init__.py index cd2388b4..c2dd0e3a 100644 --- a/accelerator/shell/__init__.py +++ b/accelerator/shell/__init__.py @@ -308,7 +308,6 @@ def _unesc(m): return _unesc_v.get(v.lower(), v) def parse_user_config(): - from accelerator.compat import open from configparser import ConfigParser from os import environ fns = [] diff --git a/accelerator/test_methods/a_test_urd.py b/accelerator/test_methods/a_test_urd.py index ae305d1b..67319798 100644 --- a/accelerator/test_methods/a_test_urd.py +++ b/accelerator/test_methods/a_test_urd.py @@ -29,7 +29,7 @@ command_prefix=['ax', '--config', '/some/path/here'], ) -from accelerator.compat import open, url_quote_more +from accelerator.compat import url_quote_more from accelerator.error import UrdPermissionError, UrdConflictError from accelerator.unixhttp import call from subprocess import Popen From 1f1e1130331149cd81124672876b03ca93ec32e1 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?= Date: Thu, 24 Jul 2025 13:55:13 +0200 Subject: [PATCH 09/18] [setup] do not import open from io This is only for Python 2 compatibility, which we no longer need. We can use the built-in without risk. --- setup.py | 1 - 1 file changed, 1 deletion(-) diff --git a/setup.py b/setup.py index 26549c3e..74f8f3fa 100755 --- a/setup.py +++ b/setup.py @@ -28,7 +28,6 @@ import os from datetime import datetime from subprocess import check_output, check_call, CalledProcessError -from io import open import re import sys From 89d1238a00855061fa229278ce6c7cd62d884766 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?= Date: Thu, 24 Jul 2025 13:47:26 +0200 Subject: [PATCH 10/18] [accelerator] drop usage of compat.unicode This is legacy from when Python (<2) was dumber. There's no need to keep that now. The definition in compat is kept for backwards compatibility. --- accelerator/build.py | 4 ++-- accelerator/compat.py | 2 +- accelerator/dataset.py | 18 +++++++++--------- accelerator/deptree.py | 4 ++-- accelerator/extras.py | 6 +++--- accelerator/graph.py | 4 ++-- accelerator/job.py | 12 ++++++------ accelerator/methods.py | 4 ++-- accelerator/server.py | 4 ++-- accelerator/setupfile.py | 4 ++-- accelerator/shell/grep.py | 16 ++++++++-------- .../standard_methods/a_dataset_fanout.py | 4 ++-- .../a_dataset_fanout_collect.py | 4 ++-- accelerator/standard_methods/a_dataset_type.py | 4 ++-- .../standard_methods/c_backend_support.py | 6 +++--- .../test_methods/a_test_board_metadata.py | 6 +++--- .../test_methods/a_test_dataset_fanout.py | 3 +-- .../test_methods/a_test_job_save_background.py | 3 +-- accelerator/urd.py | 12 ++++++------ accelerator/web.py | 4 +--- 20 files changed, 60 insertions(+), 64 deletions(-) diff --git a/accelerator/build.py b/accelerator/build.py index 2e8387b4..555a5d5f 100644 --- a/accelerator/build.py +++ b/accelerator/build.py @@ -38,7 +38,7 @@ from importlib import import_module from argparse import RawTextHelpFormatter -from accelerator.compat import unicode, str_types +from accelerator.compat import str_types from accelerator.compat import urlencode from accelerator.compat import getarglist @@ -410,7 +410,7 @@ def __bool__(self): def _urd_typeify(d): if isinstance(d, str): d = json.loads(d) - if not d or isinstance(d, unicode): + if not d or isinstance(d, str): return d res = DotDict() for k, v in d.items(): diff --git a/accelerator/compat.py b/accelerator/compat.py index 37e6cabe..c1534d89 100644 --- a/accelerator/compat.py +++ b/accelerator/compat.py @@ -80,7 +80,7 @@ def uni(s): return s.decode('utf-8') except UnicodeDecodeError: return s.decode('iso-8859-1') - return unicode(s) + return str(s) def url_quote_more(s): return quote_plus(s).replace('+', '%20') diff --git a/accelerator/dataset.py b/accelerator/dataset.py index 436e1eb7..186d40f7 100644 --- a/accelerator/dataset.py +++ b/accelerator/dataset.py @@ -34,7 +34,7 @@ from math import isnan import datetime -from accelerator.compat import unicode, uni, ifilter, imap, iteritems +from accelerator.compat import uni, ifilter, imap, iteritems from accelerator.compat import builtins, getarglist, izip, izip_longest from accelerator.compat import str_types, int_types, FileNotFoundError @@ -138,13 +138,13 @@ def __new__(cls, type, backing_type, name, location, min, max, offsets): none_support = not backing_type.startswith('bits') return _DatasetColumn_3_1(type, backing_type, name, location, min, max, offsets, none_support) -class _New_dataset_marker(unicode): pass +class _New_dataset_marker(str): pass _new_dataset_marker = _New_dataset_marker('new') _no_override = object() _ds_cache = {} def _ds_load(obj): - n = unicode(obj) + n = str(obj) if n not in _ds_cache: fn = obj.job.filename(obj._name('pickle')) if not os.path.exists(fn): @@ -179,7 +179,7 @@ def _namechk(name): def _fs_name(name): return 'DS/' + ''.join(_dir_name_blacklist.get(c, c) for c in name) -class Dataset(unicode): +class Dataset(str): """ Represents a dataset. Is also a string 'jobid/name', or just 'jobid' if name is 'default' (for better backwards compatibility). @@ -193,7 +193,7 @@ class Dataset(unicode): You can also pass jobid={jid: dsname} to resolve dsname from the datasets passed to jid. This gives NoDataset if that option was unset. - These decay to a (unicode) string when pickled. + These decay to a string when pickled. """ __slots__ = ('name', 'quoted', 'job', 'fs_name', '_data', '_cache', '_job_version',) @@ -227,7 +227,7 @@ def __new__(cls, jobid, name=None): fullname = job else: fullname = '%s/%s' % (job, name,) - obj = unicode.__new__(cls, fullname) + obj = str.__new__(cls, fullname) obj.name = name obj.quoted = quote('%s/%s' % (job, name,)) obj._job_version = 4 # hopefully @@ -260,7 +260,7 @@ def __new__(cls, jobid, name=None): # Look like a string after pickling def __reduce__(self): - return unicode, (unicode(self),) + return str, (str(self),) @property def columns(self): @@ -1056,7 +1056,7 @@ def _update_caches(self): if cache_distance == 64: cache_distance = 0 chain = self.chain(64) - self._data['cache'] = tuple((unicode(d), d._data) for d in chain[:-1]) + self._data['cache'] = tuple((str(d), d._data) for d in chain[:-1]) self._data['cache_distance'] = cache_distance def _maybe_merge(self, n): @@ -1759,7 +1759,7 @@ class NoDataset(Dataset): __slots__ = () def __new__(cls): - return unicode.__new__(cls, '') + return str.__new__(cls, '') # functions you shouldn't call on this append = iterate = iterate_chain = iterate_list = link_to_here = merge = new = None diff --git a/accelerator/deptree.py b/accelerator/deptree.py index 806b8305..08dd1680 100644 --- a/accelerator/deptree.py +++ b/accelerator/deptree.py @@ -28,7 +28,7 @@ from pathlib import Path, PosixPath, PurePath, PurePosixPath import sys -from accelerator.compat import iteritems, itervalues, first_value, str_types, int_types, num_types, unicode +from accelerator.compat import iteritems, itervalues, first_value, str_types, int_types, num_types from accelerator.extras import OptionEnum, OptionEnumValue, _OptionString, OptionDefault, RequiredOption, typing_conv from accelerator.job import JobWithFile @@ -156,7 +156,7 @@ def convert(default_v, v): if not v: raise OptionException('Option %s on method %s requires a non-empty string value' % (k, method,)) return v - if isinstance(default_v, unicode) and isinstance(v, bytes): + if isinstance(default_v, str) and isinstance(v, bytes): return v.decode('utf-8') return type(default_v)(v) if (isinstance(default_v, type) and isinstance(v, typefuzz(default_v))) or isinstance(v, typefuzz(type(default_v))): diff --git a/accelerator/extras.py b/accelerator/extras.py index 75fd3a42..a8314a0a 100644 --- a/accelerator/extras.py +++ b/accelerator/extras.py @@ -33,7 +33,7 @@ import sys from accelerator.compat import pickle, izip, iteritems, first_value -from accelerator.compat import num_types, unicode, str_types +from accelerator.compat import num_types, str_types from accelerator.error import AcceleratorError from accelerator.job import Job, JobWithFile @@ -257,7 +257,7 @@ def json_save(variable, filename='result.json', sliceno=None, sort_keys=True, _e return _SavedFile(filename, sliceno, json_load) def _unicode_as_utf8bytes(obj): - if isinstance(obj, unicode): + if isinstance(obj, str): return obj.encode('utf-8') elif isinstance(obj, dict): return DotDict((_unicode_as_utf8bytes(k), _unicode_as_utf8bytes(v)) for k, v in iteritems(obj)) @@ -281,7 +281,7 @@ def json_load(filename='result.json', jobid=None, sliceno=None, unicode_as_utf8b def quote(s): """Quote s unless it looks fine without""" - s = unicode(s) + s = str(s) r = repr(s) if s and len(s) + 2 == len(r) and not any(c.isspace() for c in s): return s diff --git a/accelerator/graph.py b/accelerator/graph.py index 5a371754..42ca3984 100644 --- a/accelerator/graph.py +++ b/accelerator/graph.py @@ -23,7 +23,7 @@ from datetime import datetime from accelerator import JobWithFile, Job from accelerator.dataset import Dataset -from accelerator.compat import unicode, FileNotFoundError +from accelerator.compat import FileNotFoundError MAXANGLE = 45 * pi / 180 @@ -74,7 +74,7 @@ def dsdeps(ds): return res -class WrapperNode(unicode): +class WrapperNode(str): def __init__(self, payload): self.payload = payload self.level = 0 diff --git a/accelerator/job.py b/accelerator/job.py index 31a92787..d79237f4 100644 --- a/accelerator/job.py +++ b/accelerator/job.py @@ -27,7 +27,7 @@ from functools import wraps from pathlib import Path -from accelerator.compat import unicode, iteritems, FileNotFoundError +from accelerator.compat import iteritems, FileNotFoundError from accelerator.error import NoSuchJobError, NoSuchWorkdirError, NoSuchDatasetError, AcceleratorError @@ -61,7 +61,7 @@ def wrapper(self): _cache = {} _nodefault = object() -class Job(unicode): +class Job(str): """ A string that is a jobid, but also has some extra properties: .method The job method (can be the "name" when from build or urd). @@ -82,7 +82,7 @@ class Job(unicode): .link_result to put a link in result_directory that points to a file in this job. .link_to_here to expose a subjob result in its parent. - Decays to a (unicode) string when pickled. + Decays to a string when pickled. """ __slots__ = ('workdir', 'number', '_cache') @@ -91,7 +91,7 @@ def __new__(cls, jobid, method=None): k = (jobid, method) if k in _cache: return _cache[k] - obj = unicode.__new__(cls, jobid) + obj = str.__new__(cls, jobid) try: obj.workdir, tmp = jobid.rsplit('-', 1) obj.number = int(tmp) @@ -318,7 +318,7 @@ def chain(self, length=-1, reverse=False, stop_job=None): # Look like a string after pickling def __reduce__(self): - return unicode, (unicode(self),) + return str, (str(self),) class CurrentJob(Job): @@ -440,7 +440,7 @@ class NoJob(Job): number = version = -1 def __new__(cls): - return unicode.__new__(cls, '') + return str.__new__(cls, '') def dataset(self, name='default'): raise NoSuchDatasetError('NoJob has no datasets') diff --git a/accelerator/methods.py b/accelerator/methods.py index ca7afd0e..08bc78b3 100644 --- a/accelerator/methods.py +++ b/accelerator/methods.py @@ -32,7 +32,7 @@ from importlib import import_module from accelerator.compat import iteritems, itervalues, first_value -from accelerator.compat import NoneType, unicode, monotonic +from accelerator.compat import NoneType, monotonic from accelerator.colourwrapper import colour from accelerator.error import AcceleratorError @@ -186,7 +186,7 @@ def fixup(item): return type(item)(l) if isinstance(item, (type, OptionEnum)): return None - assert isinstance(item, (bytes, unicode, int, float, bool, OptionEnum, NoneType, datetime.datetime, datetime.date, datetime.time, datetime.timedelta, pathlib.PosixPath, pathlib.PurePosixPath,)), type(item) + assert isinstance(item, (bytes, str, int, float, bool, OptionEnum, NoneType, datetime.datetime, datetime.date, datetime.time, datetime.timedelta, pathlib.PosixPath, pathlib.PurePosixPath,)), type(item) return item def fixup0(item): if isinstance(item, RequiredOption): diff --git a/accelerator/server.py b/accelerator/server.py index c487c97d..0c92d37d 100644 --- a/accelerator/server.py +++ b/accelerator/server.py @@ -36,7 +36,7 @@ import random import atexit -from accelerator.compat import unicode, monotonic +from accelerator.compat import monotonic from accelerator.web import ThreadedHTTPServer, ThreadedUnixHTTPServer, BaseWebHandler @@ -80,7 +80,7 @@ def do_response(self, code, content_type, body): def encode_body(self, body): if isinstance(body, bytes): return body - if isinstance(body, unicode): + if isinstance(body, str): return body.encode('utf-8') return json_encode(body) diff --git a/accelerator/setupfile.py b/accelerator/setupfile.py index ce0ed0b6..c22b214f 100644 --- a/accelerator/setupfile.py +++ b/accelerator/setupfile.py @@ -28,7 +28,7 @@ from datetime import datetime, date, time, timedelta from pathlib import PosixPath, PurePosixPath -from accelerator.compat import iteritems, unicode, uni +from accelerator.compat import iteritems, uni from accelerator.error import AcceleratorError, NoSuchJobError from accelerator.extras import DotDict, json_load, json_save, json_encode @@ -130,7 +130,7 @@ def copy_json_safe(src): elif isinstance(src, timedelta): return src.total_seconds() else: - assert isinstance(src, (str, unicode, int, float, bool)) or src is None, "%s not supported in data" % (type(src),) + assert isinstance(src, (str, int, float, bool)) or src is None, "%s not supported in data" % (type(src),) return src def encode_setup(data, sort_keys=True, as_str=False): diff --git a/accelerator/shell/grep.py b/accelerator/shell/grep.py index 9b1b3d0f..98f92a49 100644 --- a/accelerator/shell/grep.py +++ b/accelerator/shell/grep.py @@ -36,7 +36,7 @@ import operator import signal -from accelerator.compat import unicode, izip +from accelerator.compat import izip from accelerator.compat import izip_longest from accelerator.compat import monotonic from accelerator.compat import num_types @@ -69,7 +69,7 @@ def number_or_None(obj): # Base 16 has to be handled separately, because using 0 will # error on numbers starting with 0 (on python 3). # But we have to check for 0x, so things like "a" are not accepted. - if (isinstance(obj, unicode) and '0x' in obj) or (isinstance(obj, bytes) and b'0x' in obj): + if (isinstance(obj, str) and '0x' in obj) or (isinstance(obj, bytes) and b'0x' in obj): try: return int(obj, 16) except ValueError: @@ -1039,9 +1039,9 @@ def show(lineno, items): if args.show_sliceno and args.roundrobin: (prefix['sliceno'], lineno), items = items if only_matching == 'part': - items = [filter_item(unicode(item)) for item in items] + items = [filter_item(str(item)) for item in items] if only_matching == 'columns': - d = {k: v for k, v in zip(used_columns, items) if filter_item(unicode(v))} + d = {k: v for k, v in zip(used_columns, items) if filter_item(str(v))} else: d = dict(zip(used_columns, items)) if args.show_lineno: @@ -1063,10 +1063,10 @@ def show(lineno, items): data = list(prefix) if args.show_sliceno and args.roundrobin: (sliceno, lineno), items = items - data[-1] = unicode(sliceno) + data[-1] = str(sliceno) if args.show_lineno: - data.append(unicode(lineno)) - show_items = map(unicode, items) + data.append(str(lineno)) + show_items = map(str, items) if only_matching: if only_matching == 'columns': show_items = (item if filter_item(item) else '' for item in show_items) @@ -1183,7 +1183,7 @@ def mk_slicelineno_iter(): if args.numeric: fmtfix = number_or_None else: - fmtfix = unicode + fmtfix = str if args.unique: if args.unique is True: # all columns care_mask = [True] * len(used_columns) diff --git a/accelerator/standard_methods/a_dataset_fanout.py b/accelerator/standard_methods/a_dataset_fanout.py index f7dd8e6a..464f5b2f 100644 --- a/accelerator/standard_methods/a_dataset_fanout.py +++ b/accelerator/standard_methods/a_dataset_fanout.py @@ -29,7 +29,7 @@ import itertools import re -from accelerator.compat import unicode, izip +from accelerator.compat import izip from accelerator import OptionString, NoSuchDatasetError from accelerator import subjobs, status @@ -123,4 +123,4 @@ def analysis(sliceno, prepare_res): # we can't just use chain.iterate because of protections against changing types with copy_mode values_it = itertools.chain.from_iterable(ds.iterate(sliceno, columns, copy_mode=True, status_reporting=False) for ds in chain) for key, values in izip(key_it, values_it): - writers[unicode(key)].write(*values) + writers[str(key)].write(*values) diff --git a/accelerator/standard_methods/a_dataset_fanout_collect.py b/accelerator/standard_methods/a_dataset_fanout_collect.py index 8cb4e00d..db10b041 100644 --- a/accelerator/standard_methods/a_dataset_fanout_collect.py +++ b/accelerator/standard_methods/a_dataset_fanout_collect.py @@ -24,7 +24,7 @@ ''' from accelerator import OptionString -from accelerator.compat import unicode, imap +from accelerator.compat import imap options = { @@ -39,7 +39,7 @@ def analysis(sliceno): chain = datasets.source.chain(stop_ds={jobs.previous: 'source'}, length=options.length) - return set(imap(unicode, chain.iterate(sliceno, options.column))) + return set(imap(str, chain.iterate(sliceno, options.column))) def synthesis(analysis_res): return analysis_res.merge_auto() diff --git a/accelerator/standard_methods/a_dataset_type.py b/accelerator/standard_methods/a_dataset_type.py index f9514f45..7bfa5cd0 100644 --- a/accelerator/standard_methods/a_dataset_type.py +++ b/accelerator/standard_methods/a_dataset_type.py @@ -29,7 +29,7 @@ from shutil import copyfileobj from struct import Struct -from accelerator.compat import unicode, itervalues +from accelerator.compat import itervalues from accelerator.extras import OptionEnum, DotDict, quote from accelerator.dsutil import typed_writer, typed_reader @@ -490,7 +490,7 @@ def one_column(vars, colname, coltype, out_fns, for_hasher=False): else: default_value_is_None = False if default_value != cstuff.NULL: - if isinstance(default_value, unicode): + if isinstance(default_value, str): default_value = default_value.encode("utf-8") default_len = len(default_value) c = getattr(cstuff.backend, 'convert_column_' + cfunc) diff --git a/accelerator/standard_methods/c_backend_support.py b/accelerator/standard_methods/c_backend_support.py index 2f8e29a4..c682dcde 100644 --- a/accelerator/standard_methods/c_backend_support.py +++ b/accelerator/standard_methods/c_backend_support.py @@ -26,7 +26,7 @@ from importlib import import_module from collections import namedtuple -from accelerator.compat import unicode, str_types +from accelerator.compat import str_types _prologue_code_template = r''' @@ -127,7 +127,7 @@ def init(name, hash, protos, extra_protos, functions): def mk_uint64(count=1): return [0] * count def str2c(s): - if isinstance(s, unicode): + if isinstance(s, str): s = s.encode('utf-8') return s else: @@ -139,7 +139,7 @@ def str2c(s): def mk_uint64(count=1): return ffi.new('uint64_t []', [0] * count) def str2c(s): - if isinstance(s, unicode): + if isinstance(s, str): s = s.encode('utf-8') return ffi.new('char []', s) diff --git a/accelerator/test_methods/a_test_board_metadata.py b/accelerator/test_methods/a_test_board_metadata.py index 5ce42908..beb7ac04 100644 --- a/accelerator/test_methods/a_test_board_metadata.py +++ b/accelerator/test_methods/a_test_board_metadata.py @@ -29,7 +29,7 @@ command_prefix=['ax', '--config', '/some/path/here'], ) -from accelerator.compat import url_quote_more, urlopen, Request, HTTPError, unicode +from accelerator.compat import url_quote_more, urlopen, Request, HTTPError from subprocess import Popen, check_output import os @@ -77,9 +77,9 @@ def get(filename): extra_metadata = br'{"job":"/\n/DoES/NoT.EXIST/NOPE","setup_hash":"nah","host":"cough","method":"none","time":0}' def mk_meta(prefix_a, prefix_b=b'', suffix=b'', offset=0): data = extra_metadata + suffix - if isinstance(prefix_a, unicode): + if isinstance(prefix_a, str): return struct.pack(prefix_a, len(data) + len(prefix_b) + offset) + prefix_b + data - elif isinstance(prefix_b, unicode): + elif isinstance(prefix_b, str): return prefix_a + struct.pack(prefix_b, len(data) + len(prefix_a) + offset) + data else: return prefix_a + prefix_b + extra_metadata + suffix diff --git a/accelerator/test_methods/a_test_dataset_fanout.py b/accelerator/test_methods/a_test_dataset_fanout.py index 1919eff3..5ba59597 100644 --- a/accelerator/test_methods/a_test_dataset_fanout.py +++ b/accelerator/test_methods/a_test_dataset_fanout.py @@ -26,7 +26,6 @@ ''' from accelerator import subjobs -from accelerator.compat import unicode from itertools import cycle @@ -184,7 +183,7 @@ def chk(job, colnames, types, ds2lines, previous={}, hashlabel=None): cycle(['int64', 'int32']), cycle(['unicode', 'ascii']), )): - data = [('data',) + (ix + 1000,) * 4 + (unicode(ix),)] + data = [('data',) + (ix + 1000,) * 4 + (str(ix),)] want_data.append(data[0][1:]) all_types.append( mk('all types %d' % (ix,), types, data, previous=previous) diff --git a/accelerator/test_methods/a_test_job_save_background.py b/accelerator/test_methods/a_test_job_save_background.py index 76603b7d..cd9b13a8 100644 --- a/accelerator/test_methods/a_test_job_save_background.py +++ b/accelerator/test_methods/a_test_job_save_background.py @@ -37,7 +37,6 @@ options = {'sleeptime': 0.5} from accelerator.compat import monotonic -from accelerator.compat import unicode import time # This pickles as a string, but slowly. @@ -51,7 +50,7 @@ def __init__(self, text, sleeptime): def __reduce__(self): time.sleep(self.sleeptime) - return unicode, (unicode(self.text),) + return str, (str(self.text),) # This is a True boolean that takes a long time to evaluate. # It's a hack to make json encoding slow. diff --git a/accelerator/urd.py b/accelerator/urd.py index 11cc393b..63be7362 100644 --- a/accelerator/urd.py +++ b/accelerator/urd.py @@ -38,7 +38,7 @@ import os import signal -from accelerator.compat import iteritems, itervalues, unicode +from accelerator.compat import iteritems, itervalues from accelerator.colourwrapper import colour from accelerator.shell.parser import ArgumentParser from accelerator.unixhttp import WaitressServer @@ -60,7 +60,7 @@ def joblistlike(jl): assert isinstance(v, (list, tuple)), v assert len(v) == 2, v for s in v: - assert isinstance(s, unicode), s + assert isinstance(s, str), s return True @@ -234,9 +234,9 @@ def _parse_truncate(self, line): def _validate_data(self, data, with_deps=True): if with_deps: assert set(data) == {'timestamp', 'joblist', 'caption', 'user', 'build', 'deps', 'flags', 'build_job',} - assert isinstance(data.user, unicode) - assert isinstance(data.build, unicode) - assert isinstance(data.build_job, unicode) + assert isinstance(data.user, str) + assert isinstance(data.build, str) + assert isinstance(data.build_job, str) assert isinstance(data.deps, dict) for v in itervalues(data.deps): assert isinstance(v, dict) @@ -245,7 +245,7 @@ def _validate_data(self, data, with_deps=True): assert set(data) == {'timestamp', 'joblist', 'caption',} assert joblistlike(data.joblist), data.joblist assert data.joblist - assert isinstance(data.caption, unicode) + assert isinstance(data.caption, str) data.timestamp = TimeStamp(data.timestamp) def _serialise(self, action, data): diff --git a/accelerator/web.py b/accelerator/web.py index ffa1bf08..6a228484 100644 --- a/accelerator/web.py +++ b/accelerator/web.py @@ -18,8 +18,6 @@ # # ############################################################################ -from accelerator.compat import unicode - from socketserver import ThreadingMixIn from http.server import HTTPServer, BaseHTTPRequestHandler from socketserver import UnixStreamServer @@ -89,7 +87,7 @@ def _bad_request(self): def argdec(self, v): if self.unicode_args: - if type(v) is unicode: return v + if type(v) is str: return v try: return v.decode("utf-8") except Exception: From 15f1680d5d66e7cd408c0b7ce898bb02040ea54d Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?= Date: Tue, 29 Jul 2025 12:05:07 +0200 Subject: [PATCH 11/18] [accelerator] drop "from __future__" imports All those used: division, absolute_import, print_function, unicode_literals are mandatory since Python 3.0. Given we support only from 3.6, removing these imports is a nice cleanup to reduce code clutter with things that are unnecessary. --- accelerator/board.py | 2 -- accelerator/build.py | 3 --- accelerator/colourwrapper.py | 4 ---- accelerator/compat.py | 4 ---- accelerator/configfile.py | 3 --- accelerator/control.py | 3 --- accelerator/database.py | 3 --- accelerator/dataset.py | 4 ---- accelerator/dependency.py | 3 --- accelerator/deptree.py | 3 --- accelerator/dispatch.py | 3 --- accelerator/dsutil.py | 3 --- accelerator/error.py | 4 ---- accelerator/extras.py | 3 --- accelerator/iowrapper.py | 4 ---- accelerator/launch.py | 3 --- accelerator/metadata.py | 2 -- accelerator/methods.py | 3 --- accelerator/mp.py | 3 --- accelerator/runner.py | 3 --- accelerator/server.py | 3 --- accelerator/setupfile.py | 3 --- accelerator/shell/__init__.py | 4 ---- accelerator/shell/ds.py | 2 -- accelerator/shell/gc.py | 2 -- accelerator/shell/grep.py | 2 -- accelerator/shell/hist.py | 4 ---- accelerator/shell/init.py | 4 ---- accelerator/shell/job.py | 4 ---- accelerator/shell/lined.py | 2 -- accelerator/shell/method.py | 4 ---- accelerator/shell/parser.py | 2 -- accelerator/shell/script.py | 4 ---- accelerator/shell/sherlock.py | 2 -- accelerator/shell/status.py | 3 --- accelerator/shell/urd.py | 4 ---- accelerator/shell/workdir.py | 4 ---- accelerator/standard_methods/a_csvexport.py | 3 --- accelerator/standard_methods/a_csvimport.py | 4 ---- accelerator/standard_methods/a_csvimport_zip.py | 5 ----- accelerator/standard_methods/a_dataset_checksum.py | 4 ---- accelerator/standard_methods/a_dataset_checksum_chain.py | 4 ---- accelerator/standard_methods/a_dataset_filter_columns.py | 2 -- accelerator/standard_methods/a_dataset_hashpart.py | 3 --- accelerator/standard_methods/a_dataset_sort.py | 4 ---- accelerator/standard_methods/a_dataset_type.py | 4 ---- accelerator/standard_methods/a_dataset_unroundrobin.py | 3 --- accelerator/standard_methods/c_backend_support.py | 4 ---- accelerator/standard_methods/csvimport.py | 4 ---- accelerator/standard_methods/dataset_type.py | 4 ---- accelerator/statmsg.py | 3 --- accelerator/test_methods/a_test_board_metadata.py | 4 ---- accelerator/test_methods/a_test_build_kws.py | 4 ---- accelerator/test_methods/a_test_compare_datasets.py | 4 ---- accelerator/test_methods/a_test_csvexport_all_coltypes.py | 4 ---- accelerator/test_methods/a_test_csvexport_chains.py | 4 ---- accelerator/test_methods/a_test_csvexport_naming.py | 4 ---- accelerator/test_methods/a_test_csvexport_separators.py | 4 ---- accelerator/test_methods/a_test_csvimport_corner_cases.py | 4 ---- accelerator/test_methods/a_test_csvimport_separators.py | 4 ---- accelerator/test_methods/a_test_csvimport_slicing.py | 2 -- accelerator/test_methods/a_test_csvimport_zip.py | 4 ---- accelerator/test_methods/a_test_dataset_callbacks.py | 4 ---- accelerator/test_methods/a_test_dataset_checksum.py | 4 ---- accelerator/test_methods/a_test_dataset_column_names.py | 4 ---- accelerator/test_methods/a_test_dataset_fanout.py | 4 ---- accelerator/test_methods/a_test_dataset_filter_columns.py | 4 ---- accelerator/test_methods/a_test_dataset_in_prepare.py | 4 ---- accelerator/test_methods/a_test_dataset_merge.py | 4 ---- accelerator/test_methods/a_test_dataset_names.py | 4 ---- accelerator/test_methods/a_test_dataset_nan.py | 4 ---- accelerator/test_methods/a_test_dataset_overwrite.py | 4 ---- accelerator/test_methods/a_test_dataset_parsing_writer.py | 4 ---- accelerator/test_methods/a_test_dataset_range.py | 4 ---- accelerator/test_methods/a_test_dataset_roundrobin.py | 4 ---- accelerator/test_methods/a_test_dataset_slice.py | 4 ---- accelerator/test_methods/a_test_dataset_type_None.py | 2 -- accelerator/test_methods/a_test_dataset_type_chaining.py | 4 ---- accelerator/test_methods/a_test_dataset_type_corner_cases.py | 4 ---- accelerator/test_methods/a_test_dataset_type_hashing.py | 4 ---- accelerator/test_methods/a_test_dataset_type_minmax.py | 4 ---- accelerator/test_methods/a_test_dataset_unroundrobin.py | 4 ---- .../test_methods/a_test_dataset_unroundrobin_trigger.py | 4 ---- accelerator/test_methods/a_test_datasetwriter.py | 4 ---- accelerator/test_methods/a_test_datasetwriter_copy.py | 4 ---- .../test_methods/a_test_datasetwriter_missing_slices.py | 4 ---- accelerator/test_methods/a_test_datasetwriter_parent.py | 4 ---- accelerator/test_methods/a_test_datasetwriter_verify.py | 4 ---- accelerator/test_methods/a_test_datetime.py | 4 ---- accelerator/test_methods/a_test_hashlabel.py | 4 ---- accelerator/test_methods/a_test_hashpart.py | 4 ---- accelerator/test_methods/a_test_jobchain.py | 4 ---- accelerator/test_methods/a_test_jobwithfile.py | 4 ---- accelerator/test_methods/a_test_json.py | 4 ---- accelerator/test_methods/a_test_nan.py | 4 ---- accelerator/test_methods/a_test_number.py | 4 ---- accelerator/test_methods/a_test_optionenum.py | 4 ---- accelerator/test_methods/a_test_output.py | 4 ---- accelerator/test_methods/a_test_rechain.py | 4 ---- accelerator/test_methods/a_test_register_file.py | 4 ---- accelerator/test_methods/a_test_register_file_auto.py | 4 ---- accelerator/test_methods/a_test_register_file_auto_2.py | 4 ---- accelerator/test_methods/a_test_register_file_manual.py | 4 ---- accelerator/test_methods/a_test_selfchain.py | 4 ---- accelerator/test_methods/a_test_shell_commands.py | 4 ---- accelerator/test_methods/a_test_shell_config.py | 4 ---- accelerator/test_methods/a_test_shell_data.py | 4 ---- accelerator/test_methods/a_test_shell_ds.py | 5 ----- accelerator/test_methods/a_test_shell_grep.py | 4 ---- accelerator/test_methods/a_test_shell_job.py | 4 ---- accelerator/test_methods/a_test_sort_chaining.py | 4 ---- accelerator/test_methods/a_test_sort_stability.py | 4 ---- accelerator/test_methods/a_test_sort_trigger.py | 4 ---- accelerator/test_methods/a_test_sorting.py | 4 ---- accelerator/test_methods/a_test_sorting_gendata.py | 4 ---- accelerator/test_methods/a_test_status_in_exceptions.py | 4 ---- accelerator/test_methods/a_test_subjobs_nesting.py | 4 ---- accelerator/test_methods/a_test_subjobs_type.py | 4 ---- accelerator/test_methods/a_test_summary.py | 4 ---- accelerator/test_methods/a_test_urd.py | 4 ---- accelerator/test_methods/build_tests.py | 4 ---- accelerator/test_methods/test_data.py | 4 ---- accelerator/unixhttp.py | 3 --- accelerator/urd.py | 4 ---- accelerator/workspace.py | 3 --- dsutil/test.py | 2 -- setup.py | 2 -- 127 files changed, 462 deletions(-) diff --git a/accelerator/board.py b/accelerator/board.py index bb677cd2..e7a850b8 100644 --- a/accelerator/board.py +++ b/accelerator/board.py @@ -18,8 +18,6 @@ # # ############################################################################ -from __future__ import print_function - import bottle import json import sys diff --git a/accelerator/build.py b/accelerator/build.py index 555a5d5f..c1d1b1d1 100644 --- a/accelerator/build.py +++ b/accelerator/build.py @@ -20,9 +20,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - import sys import os import io diff --git a/accelerator/colourwrapper.py b/accelerator/colourwrapper.py index b7fddce7..bd46a35e 100644 --- a/accelerator/colourwrapper.py +++ b/accelerator/colourwrapper.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - import sys, os from functools import partial diff --git a/accelerator/compat.py b/accelerator/compat.py index c1534d89..826ffb1d 100644 --- a/accelerator/compat.py +++ b/accelerator/compat.py @@ -20,10 +20,6 @@ # a few things that differ between python2 and python3 -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - import sys try: from setproctitle import setproctitle as _setproctitle, getproctitle diff --git a/accelerator/configfile.py b/accelerator/configfile.py index b364e1fa..10f7ad35 100644 --- a/accelerator/configfile.py +++ b/accelerator/configfile.py @@ -19,9 +19,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - import re import os import shlex diff --git a/accelerator/control.py b/accelerator/control.py index 8ed8b42f..f9f0a8bf 100644 --- a/accelerator/control.py +++ b/accelerator/control.py @@ -19,9 +19,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - from threading import Thread import multiprocessing import signal diff --git a/accelerator/database.py b/accelerator/database.py index ad1668a6..089c7424 100644 --- a/accelerator/database.py +++ b/accelerator/database.py @@ -19,9 +19,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - from collections import defaultdict from collections import namedtuple from traceback import print_exc diff --git a/accelerator/dataset.py b/accelerator/dataset.py index 186d40f7..f044fe4d 100644 --- a/accelerator/dataset.py +++ b/accelerator/dataset.py @@ -20,10 +20,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - import os from keyword import kwlist from collections import namedtuple, Counter diff --git a/accelerator/dependency.py b/accelerator/dependency.py index e26a5b9d..4114cf6f 100644 --- a/accelerator/dependency.py +++ b/accelerator/dependency.py @@ -18,9 +18,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - from random import randint from collections import OrderedDict, defaultdict from itertools import combinations diff --git a/accelerator/deptree.py b/accelerator/deptree.py index 08dd1680..1dc7d8f8 100644 --- a/accelerator/deptree.py +++ b/accelerator/deptree.py @@ -19,9 +19,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - from traceback import print_exc from collections import OrderedDict from datetime import datetime, date, time, timedelta diff --git a/accelerator/dispatch.py b/accelerator/dispatch.py index 9defffd0..988a8a77 100644 --- a/accelerator/dispatch.py +++ b/accelerator/dispatch.py @@ -19,9 +19,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - import os from signal import SIGTERM, SIGKILL diff --git a/accelerator/dsutil.py b/accelerator/dsutil.py index 615bd14f..376dbe34 100644 --- a/accelerator/dsutil.py +++ b/accelerator/dsutil.py @@ -18,9 +18,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - from accelerator import _dsutil from accelerator.compat import str_types from accelerator.standard_methods._dataset_type import strptime, strptime_i diff --git a/accelerator/error.py b/accelerator/error.py index 7fd5abd1..6f738cf9 100644 --- a/accelerator/error.py +++ b/accelerator/error.py @@ -18,10 +18,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - class AcceleratorError(Exception): """Base class for all accelerator exception types""" __slots__ = () diff --git a/accelerator/extras.py b/accelerator/extras.py index a8314a0a..30bce23d 100644 --- a/accelerator/extras.py +++ b/accelerator/extras.py @@ -20,9 +20,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - import os import datetime import json diff --git a/accelerator/iowrapper.py b/accelerator/iowrapper.py index c8fb012a..96c1de73 100644 --- a/accelerator/iowrapper.py +++ b/accelerator/iowrapper.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - import os from contextlib import contextmanager from multiprocessing import Process diff --git a/accelerator/launch.py b/accelerator/launch.py index e21fa5f2..de29a6e1 100644 --- a/accelerator/launch.py +++ b/accelerator/launch.py @@ -20,9 +20,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - import os import signal import sys diff --git a/accelerator/metadata.py b/accelerator/metadata.py index 5f2af074..58b13a7a 100644 --- a/accelerator/metadata.py +++ b/accelerator/metadata.py @@ -20,8 +20,6 @@ # Functions for generating, inserting and extracting metadata about the job # that built files. -from __future__ import print_function - import json import re import socket diff --git a/accelerator/methods.py b/accelerator/methods.py index 08bc78b3..96c18424 100644 --- a/accelerator/methods.py +++ b/accelerator/methods.py @@ -20,9 +20,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - import os import sys import datetime diff --git a/accelerator/mp.py b/accelerator/mp.py index a28b8a9d..e9f5467c 100644 --- a/accelerator/mp.py +++ b/accelerator/mp.py @@ -17,9 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - import os import sys import select diff --git a/accelerator/runner.py b/accelerator/runner.py index b8518ca4..4ab6c39c 100644 --- a/accelerator/runner.py +++ b/accelerator/runner.py @@ -25,9 +25,6 @@ # Also contains the function that starts these (new_runners) and the dict # of running ones {version: Runner} -from __future__ import print_function -from __future__ import division - from importlib import import_module from types import ModuleType from traceback import print_exc diff --git a/accelerator/server.py b/accelerator/server.py index 0c92d37d..69b8a22e 100644 --- a/accelerator/server.py +++ b/accelerator/server.py @@ -19,9 +19,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - import sys import socket import traceback diff --git a/accelerator/setupfile.py b/accelerator/setupfile.py index c22b214f..28089357 100644 --- a/accelerator/setupfile.py +++ b/accelerator/setupfile.py @@ -20,9 +20,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - from collections import OrderedDict from json import dumps from datetime import datetime, date, time, timedelta diff --git a/accelerator/shell/__init__.py b/accelerator/shell/__init__.py index c2dd0e3a..4e6679ab 100644 --- a/accelerator/shell/__init__.py +++ b/accelerator/shell/__init__.py @@ -18,10 +18,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - import sys import errno import os diff --git a/accelerator/shell/ds.py b/accelerator/shell/ds.py index b633472b..b706971a 100644 --- a/accelerator/shell/ds.py +++ b/accelerator/shell/ds.py @@ -19,8 +19,6 @@ # # ############################################################################ -from __future__ import division, print_function - import sys import locale from math import ceil diff --git a/accelerator/shell/gc.py b/accelerator/shell/gc.py index 292214b3..2154e94f 100644 --- a/accelerator/shell/gc.py +++ b/accelerator/shell/gc.py @@ -17,8 +17,6 @@ # # ############################################################################ -from __future__ import print_function - from accelerator.error import AcceleratorError from accelerator.job import Job from accelerator.shell.parser import ArgumentParser diff --git a/accelerator/shell/grep.py b/accelerator/shell/grep.py index 98f92a49..c0208faf 100644 --- a/accelerator/shell/grep.py +++ b/accelerator/shell/grep.py @@ -21,8 +21,6 @@ # grep in a dataset(chain) -from __future__ import division, print_function - import sys import re import os diff --git a/accelerator/shell/hist.py b/accelerator/shell/hist.py index e94752bf..ea351a5b 100644 --- a/accelerator/shell/hist.py +++ b/accelerator/shell/hist.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import division -from __future__ import print_function -from __future__ import unicode_literals - from accelerator.colourwrapper import colour from accelerator.compat import fmt_num, num_types, int_types from accelerator.error import NoSuchWhateverError diff --git a/accelerator/shell/init.py b/accelerator/shell/init.py index 04a2f065..3f776612 100644 --- a/accelerator/shell/init.py +++ b/accelerator/shell/init.py @@ -19,10 +19,6 @@ ############################################################################ -from __future__ import print_function -from __future__ import division - - a_example = r"""description = r''' This is just an example. It doesn't even try to do anything useful. diff --git a/accelerator/shell/job.py b/accelerator/shell/job.py index 2f8084ba..3f93764b 100644 --- a/accelerator/shell/job.py +++ b/accelerator/shell/job.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - from traceback import print_exc from datetime import datetime import errno diff --git a/accelerator/shell/lined.py b/accelerator/shell/lined.py index 2856d673..1015efd7 100644 --- a/accelerator/shell/lined.py +++ b/accelerator/shell/lined.py @@ -17,8 +17,6 @@ # # ############################################################################ -from __future__ import division, print_function - from itertools import cycle import errno import os diff --git a/accelerator/shell/method.py b/accelerator/shell/method.py index 7e09dae4..ee6e5bc8 100644 --- a/accelerator/shell/method.py +++ b/accelerator/shell/method.py @@ -18,10 +18,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - from accelerator.compat import terminal_size from accelerator.unixhttp import call from accelerator.shell import printdesc diff --git a/accelerator/shell/parser.py b/accelerator/shell/parser.py index f9ae0cb8..bb1cad5d 100644 --- a/accelerator/shell/parser.py +++ b/accelerator/shell/parser.py @@ -22,8 +22,6 @@ # parsing of "job specs", including as part of a dataset name. # handles jobids, paths and method names. -from __future__ import division, print_function - import argparse import sys from os.path import join, exists, realpath, split diff --git a/accelerator/shell/script.py b/accelerator/shell/script.py index 5fef7a01..80eaff72 100644 --- a/accelerator/shell/script.py +++ b/accelerator/shell/script.py @@ -18,10 +18,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - import sys from glob import glob from os.path import dirname, basename diff --git a/accelerator/shell/sherlock.py b/accelerator/shell/sherlock.py index 21ba5812..1e04798c 100644 --- a/accelerator/shell/sherlock.py +++ b/accelerator/shell/sherlock.py @@ -17,8 +17,6 @@ # # ############################################################################ -from __future__ import print_function - from datetime import datetime import os import sys diff --git a/accelerator/shell/status.py b/accelerator/shell/status.py index fffc57ea..8470e872 100644 --- a/accelerator/shell/status.py +++ b/accelerator/shell/status.py @@ -17,8 +17,6 @@ # # ############################################################################ -from __future__ import print_function - from accelerator.build import fmttime from accelerator.error import JobError from accelerator.job import Job @@ -50,4 +48,3 @@ def main(argv, cfg): print('%s (%s)' % (status.current[1], t)) else: print_status_stacks(status.status_stacks) - diff --git a/accelerator/shell/urd.py b/accelerator/shell/urd.py index 5e34d50d..8db1c889 100644 --- a/accelerator/shell/urd.py +++ b/accelerator/shell/urd.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - import sys from os import environ from argparse import RawDescriptionHelpFormatter diff --git a/accelerator/shell/workdir.py b/accelerator/shell/workdir.py index 494e5532..79212cdb 100644 --- a/accelerator/shell/workdir.py +++ b/accelerator/shell/workdir.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - import sys import os diff --git a/accelerator/standard_methods/a_csvexport.py b/accelerator/standard_methods/a_csvexport.py index 8ef54f1e..5c59979b 100644 --- a/accelerator/standard_methods/a_csvexport.py +++ b/accelerator/standard_methods/a_csvexport.py @@ -18,9 +18,6 @@ # # ############################################################################ -from __future__ import division -from __future__ import absolute_import - description = r'''Dataset (or chain) to CSV file.''' from shutil import copyfileobj diff --git a/accelerator/standard_methods/a_csvimport.py b/accelerator/standard_methods/a_csvimport.py index a77228a3..bea51d16 100644 --- a/accelerator/standard_methods/a_csvimport.py +++ b/accelerator/standard_methods/a_csvimport.py @@ -19,10 +19,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' CSV file to dataset. diff --git a/accelerator/standard_methods/a_csvimport_zip.py b/accelerator/standard_methods/a_csvimport_zip.py index 79e02b82..6ab09acd 100644 --- a/accelerator/standard_methods/a_csvimport_zip.py +++ b/accelerator/standard_methods/a_csvimport_zip.py @@ -18,11 +18,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals -from __future__ import absolute_import - description = r''' Call csvimport on one or more files in a zip file. diff --git a/accelerator/standard_methods/a_dataset_checksum.py b/accelerator/standard_methods/a_dataset_checksum.py index 9cc3f304..0d7b25c1 100644 --- a/accelerator/standard_methods/a_dataset_checksum.py +++ b/accelerator/standard_methods/a_dataset_checksum.py @@ -18,10 +18,6 @@ # # ############################################################################ -from __future__ import division -from __future__ import print_function -from __future__ import absolute_import - description = r''' Take a dataset and make a checksum of one or more columns. diff --git a/accelerator/standard_methods/a_dataset_checksum_chain.py b/accelerator/standard_methods/a_dataset_checksum_chain.py index 2488d055..6341adbd 100644 --- a/accelerator/standard_methods/a_dataset_checksum_chain.py +++ b/accelerator/standard_methods/a_dataset_checksum_chain.py @@ -18,10 +18,6 @@ # # ############################################################################ -from __future__ import division -from __future__ import print_function -from __future__ import absolute_import - description = r''' Take a chain of datasets and make a checksum of one or more columns. See dataset_checksum.description for more information. diff --git a/accelerator/standard_methods/a_dataset_filter_columns.py b/accelerator/standard_methods/a_dataset_filter_columns.py index 7d136084..a1d43ed6 100644 --- a/accelerator/standard_methods/a_dataset_filter_columns.py +++ b/accelerator/standard_methods/a_dataset_filter_columns.py @@ -19,8 +19,6 @@ # # ############################################################################ -from __future__ import absolute_import - description = r"""Make only some columns from a dataset visible.""" from accelerator.extras import OptionDefault diff --git a/accelerator/standard_methods/a_dataset_hashpart.py b/accelerator/standard_methods/a_dataset_hashpart.py index 67132c8c..23418226 100644 --- a/accelerator/standard_methods/a_dataset_hashpart.py +++ b/accelerator/standard_methods/a_dataset_hashpart.py @@ -18,9 +18,6 @@ # # ############################################################################ -from __future__ import division -from __future__ import absolute_import - description = r''' Rewrite a dataset (or chain to previous) with new hashlabel. ''' diff --git a/accelerator/standard_methods/a_dataset_sort.py b/accelerator/standard_methods/a_dataset_sort.py index 5e85f2f0..fe4febf5 100644 --- a/accelerator/standard_methods/a_dataset_sort.py +++ b/accelerator/standard_methods/a_dataset_sort.py @@ -18,10 +18,6 @@ # # ############################################################################ -from __future__ import division -from __future__ import absolute_import -from __future__ import print_function - description = r''' Stable sort a dataset based on one or more columns. You'll have to type the sort column(s) approprietly. diff --git a/accelerator/standard_methods/a_dataset_type.py b/accelerator/standard_methods/a_dataset_type.py index 7bfa5cd0..a3f310e6 100644 --- a/accelerator/standard_methods/a_dataset_type.py +++ b/accelerator/standard_methods/a_dataset_type.py @@ -18,10 +18,6 @@ # # ############################################################################ -from __future__ import division -from __future__ import absolute_import -from __future__ import print_function - from resource import getpagesize from os import unlink from os.path import exists diff --git a/accelerator/standard_methods/a_dataset_unroundrobin.py b/accelerator/standard_methods/a_dataset_unroundrobin.py index 2d5d5018..f04a3565 100644 --- a/accelerator/standard_methods/a_dataset_unroundrobin.py +++ b/accelerator/standard_methods/a_dataset_unroundrobin.py @@ -17,9 +17,6 @@ # # ############################################################################ -from __future__ import division -from __future__ import absolute_import - description = r''' new_ds.iterate(None) gives the same order as old_ds.iterate('roundrobin'). diff --git a/accelerator/standard_methods/c_backend_support.py b/accelerator/standard_methods/c_backend_support.py index c682dcde..ecc6da59 100644 --- a/accelerator/standard_methods/c_backend_support.py +++ b/accelerator/standard_methods/c_backend_support.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - import sys import hashlib from importlib import import_module diff --git a/accelerator/standard_methods/csvimport.py b/accelerator/standard_methods/csvimport.py index d752ac42..09827c58 100644 --- a/accelerator/standard_methods/csvimport.py +++ b/accelerator/standard_methods/csvimport.py @@ -20,10 +20,6 @@ # This is a separate file from a_csvimport so setup.py can import # it and make the _csvimport module at install time. -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - from . import c_backend_support all_c_functions = r''' diff --git a/accelerator/standard_methods/dataset_type.py b/accelerator/standard_methods/dataset_type.py index 078a7eb5..f04e44e1 100644 --- a/accelerator/standard_methods/dataset_type.py +++ b/accelerator/standard_methods/dataset_type.py @@ -21,10 +21,6 @@ # This is a separate file from a_dataset_type so setup.py can import # it and make the _dataset_type module at install time. -from __future__ import print_function -from __future__ import division -from __future__ import absolute_import - from collections import namedtuple from functools import partial import sys diff --git a/accelerator/statmsg.py b/accelerator/statmsg.py index f832b6ea..60098331 100644 --- a/accelerator/statmsg.py +++ b/accelerator/statmsg.py @@ -34,9 +34,6 @@ # Several built in functions will call this for you, notably dataset # iterators and pickle load/save functions. -from __future__ import print_function -from __future__ import division - from contextlib import contextmanager from errno import ENOTCONN from functools import partial diff --git a/accelerator/test_methods/a_test_board_metadata.py b/accelerator/test_methods/a_test_board_metadata.py index beb7ac04..e0a4f88e 100644 --- a/accelerator/test_methods/a_test_board_metadata.py +++ b/accelerator/test_methods/a_test_board_metadata.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test board adding metadata to files and decoding this with "ax sherlock". ''' diff --git a/accelerator/test_methods/a_test_build_kws.py b/accelerator/test_methods/a_test_build_kws.py index 85618189..0bd18578 100644 --- a/accelerator/test_methods/a_test_build_kws.py +++ b/accelerator/test_methods/a_test_build_kws.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' This method is called to test that urd.build finds the correct target for keywords, and also that it does not accept ambiguous keywords. diff --git a/accelerator/test_methods/a_test_compare_datasets.py b/accelerator/test_methods/a_test_compare_datasets.py index 3bbee880..70cea8e8 100644 --- a/accelerator/test_methods/a_test_compare_datasets.py +++ b/accelerator/test_methods/a_test_compare_datasets.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - datasets = ("a", "b",) def analysis(sliceno): diff --git a/accelerator/test_methods/a_test_csvexport_all_coltypes.py b/accelerator/test_methods/a_test_csvexport_all_coltypes.py index 0482b5d8..ba7bdc82 100644 --- a/accelerator/test_methods/a_test_csvexport_all_coltypes.py +++ b/accelerator/test_methods/a_test_csvexport_all_coltypes.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify that all column types come out correctly in csvexport. ''' diff --git a/accelerator/test_methods/a_test_csvexport_chains.py b/accelerator/test_methods/a_test_csvexport_chains.py index 15e64c7a..9daed14d 100644 --- a/accelerator/test_methods/a_test_csvexport_chains.py +++ b/accelerator/test_methods/a_test_csvexport_chains.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify that lists of chains are handled in csvexport, including changing column types. diff --git a/accelerator/test_methods/a_test_csvexport_naming.py b/accelerator/test_methods/a_test_csvexport_naming.py index 2cbf2ef2..9e11bf65 100644 --- a/accelerator/test_methods/a_test_csvexport_naming.py +++ b/accelerator/test_methods/a_test_csvexport_naming.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify filename (sliced and unsliced) and gzip in csvexport. ''' diff --git a/accelerator/test_methods/a_test_csvexport_separators.py b/accelerator/test_methods/a_test_csvexport_separators.py index a3afda67..51eb7bb1 100644 --- a/accelerator/test_methods/a_test_csvexport_separators.py +++ b/accelerator/test_methods/a_test_csvexport_separators.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test some strange choices for separators in csvexport. ''' diff --git a/accelerator/test_methods/a_test_csvimport_corner_cases.py b/accelerator/test_methods/a_test_csvimport_corner_cases.py index b483004a..05ffa371 100644 --- a/accelerator/test_methods/a_test_csvimport_corner_cases.py +++ b/accelerator/test_methods/a_test_csvimport_corner_cases.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify various corner cases in csvimport. ''' diff --git a/accelerator/test_methods/a_test_csvimport_separators.py b/accelerator/test_methods/a_test_csvimport_separators.py index f2f78d08..b1a1a29d 100644 --- a/accelerator/test_methods/a_test_csvimport_separators.py +++ b/accelerator/test_methods/a_test_csvimport_separators.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify that various separators and line endings work in csvimport, with and without quoting. diff --git a/accelerator/test_methods/a_test_csvimport_slicing.py b/accelerator/test_methods/a_test_csvimport_slicing.py index 1e84204a..ddfb4485 100644 --- a/accelerator/test_methods/a_test_csvimport_slicing.py +++ b/accelerator/test_methods/a_test_csvimport_slicing.py @@ -17,8 +17,6 @@ # # ############################################################################ -from __future__ import unicode_literals - description = r''' Verify that csvimport puts lines in the expected slice. diff --git a/accelerator/test_methods/a_test_csvimport_zip.py b/accelerator/test_methods/a_test_csvimport_zip.py index 217d3278..67b5aa16 100644 --- a/accelerator/test_methods/a_test_csvimport_zip.py +++ b/accelerator/test_methods/a_test_csvimport_zip.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify the zip wrapper for csvimport. ''' diff --git a/accelerator/test_methods/a_test_dataset_callbacks.py b/accelerator/test_methods/a_test_dataset_callbacks.py index 0e2ba22e..8e5a45cc 100644 --- a/accelerator/test_methods/a_test_dataset_callbacks.py +++ b/accelerator/test_methods/a_test_dataset_callbacks.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Tests many variations of dataset iteration callbacks with skipping. ''' diff --git a/accelerator/test_methods/a_test_dataset_checksum.py b/accelerator/test_methods/a_test_dataset_checksum.py index 5002ce9c..6b849048 100644 --- a/accelerator/test_methods/a_test_dataset_checksum.py +++ b/accelerator/test_methods/a_test_dataset_checksum.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test dataset_checksum[_chain]. ''' diff --git a/accelerator/test_methods/a_test_dataset_column_names.py b/accelerator/test_methods/a_test_dataset_column_names.py index 312ad399..12abe9cd 100644 --- a/accelerator/test_methods/a_test_dataset_column_names.py +++ b/accelerator/test_methods/a_test_dataset_column_names.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test writing datasets with strange column names, column names whose cleaned names collide and column names used in the generated split_write function. diff --git a/accelerator/test_methods/a_test_dataset_fanout.py b/accelerator/test_methods/a_test_dataset_fanout.py index 5ba59597..b60f9d1a 100644 --- a/accelerator/test_methods/a_test_dataset_fanout.py +++ b/accelerator/test_methods/a_test_dataset_fanout.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test dataset_fanout with varying types, hashlabel and chain truncation. ''' diff --git a/accelerator/test_methods/a_test_dataset_filter_columns.py b/accelerator/test_methods/a_test_dataset_filter_columns.py index 63654f0c..7c019e76 100644 --- a/accelerator/test_methods/a_test_dataset_filter_columns.py +++ b/accelerator/test_methods/a_test_dataset_filter_columns.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test the dataset_filter_columns method. ''' diff --git a/accelerator/test_methods/a_test_dataset_in_prepare.py b/accelerator/test_methods/a_test_dataset_in_prepare.py index ebf380de..82c980ca 100644 --- a/accelerator/test_methods/a_test_dataset_in_prepare.py +++ b/accelerator/test_methods/a_test_dataset_in_prepare.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test writing a dataset in prepare, verifying that it is usable in analysis and synthesis with no manual .finish() diff --git a/accelerator/test_methods/a_test_dataset_merge.py b/accelerator/test_methods/a_test_dataset_merge.py index 7c8e0d5e..9ce4468f 100644 --- a/accelerator/test_methods/a_test_dataset_merge.py +++ b/accelerator/test_methods/a_test_dataset_merge.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test Dataset.merge() and the dataset_merge method. ''' diff --git a/accelerator/test_methods/a_test_dataset_names.py b/accelerator/test_methods/a_test_dataset_names.py index 4ad15061..844f60dc 100644 --- a/accelerator/test_methods/a_test_dataset_names.py +++ b/accelerator/test_methods/a_test_dataset_names.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify that some potentially problematic dataset names work. ''' diff --git a/accelerator/test_methods/a_test_dataset_nan.py b/accelerator/test_methods/a_test_dataset_nan.py index 7010b871..8d4f0cca 100644 --- a/accelerator/test_methods/a_test_dataset_nan.py +++ b/accelerator/test_methods/a_test_dataset_nan.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test that NaN does not end up in min/max unless it's the only value. ''' diff --git a/accelerator/test_methods/a_test_dataset_overwrite.py b/accelerator/test_methods/a_test_dataset_overwrite.py index 9b666937..8818b946 100644 --- a/accelerator/test_methods/a_test_dataset_overwrite.py +++ b/accelerator/test_methods/a_test_dataset_overwrite.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify that datasets can not be overwritten. ''' diff --git a/accelerator/test_methods/a_test_dataset_parsing_writer.py b/accelerator/test_methods/a_test_dataset_parsing_writer.py index c2645019..eb349d31 100644 --- a/accelerator/test_methods/a_test_dataset_parsing_writer.py +++ b/accelerator/test_methods/a_test_dataset_parsing_writer.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Tests the parsed:type writers. With plain values, parsable values and unparsable values. diff --git a/accelerator/test_methods/a_test_dataset_range.py b/accelerator/test_methods/a_test_dataset_range.py index 6a9d6d6e..75fb4c53 100644 --- a/accelerator/test_methods/a_test_dataset_range.py +++ b/accelerator/test_methods/a_test_dataset_range.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test the range argument to the dataset iteration functions and chain.with_column(). diff --git a/accelerator/test_methods/a_test_dataset_roundrobin.py b/accelerator/test_methods/a_test_dataset_roundrobin.py index 1af0e457..9df3f788 100644 --- a/accelerator/test_methods/a_test_dataset_roundrobin.py +++ b/accelerator/test_methods/a_test_dataset_roundrobin.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test sliceno="roundrobin" in dataset iteration. ''' diff --git a/accelerator/test_methods/a_test_dataset_slice.py b/accelerator/test_methods/a_test_dataset_slice.py index 3c369f74..62aaeb96 100644 --- a/accelerator/test_methods/a_test_dataset_slice.py +++ b/accelerator/test_methods/a_test_dataset_slice.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test dataset iteration slicing. ''' diff --git a/accelerator/test_methods/a_test_dataset_type_None.py b/accelerator/test_methods/a_test_dataset_type_None.py index bb39b0dc..2227adb1 100644 --- a/accelerator/test_methods/a_test_dataset_type_None.py +++ b/accelerator/test_methods/a_test_dataset_type_None.py @@ -17,8 +17,6 @@ # # ############################################################################ -from __future__ import unicode_literals - description = r''' Test the +None types in dataset_type. diff --git a/accelerator/test_methods/a_test_dataset_type_chaining.py b/accelerator/test_methods/a_test_dataset_type_chaining.py index 71ac4557..9aec167a 100644 --- a/accelerator/test_methods/a_test_dataset_type_chaining.py +++ b/accelerator/test_methods/a_test_dataset_type_chaining.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify the various dataset_type chaining options: Building a chain with and without extra datasets in the source. diff --git a/accelerator/test_methods/a_test_dataset_type_corner_cases.py b/accelerator/test_methods/a_test_dataset_type_corner_cases.py index 44d5ace0..65a66320 100644 --- a/accelerator/test_methods/a_test_dataset_type_corner_cases.py +++ b/accelerator/test_methods/a_test_dataset_type_corner_cases.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify various corner cases in dataset_type. ''' diff --git a/accelerator/test_methods/a_test_dataset_type_hashing.py b/accelerator/test_methods/a_test_dataset_type_hashing.py index b1243182..24e98346 100644 --- a/accelerator/test_methods/a_test_dataset_type_hashing.py +++ b/accelerator/test_methods/a_test_dataset_type_hashing.py @@ -18,10 +18,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify that using dataset_type with a hashlabel gives the same result as first typing and then rehashing for various hashlabel types, including diff --git a/accelerator/test_methods/a_test_dataset_type_minmax.py b/accelerator/test_methods/a_test_dataset_type_minmax.py index c8d7d67c..f1e1a281 100644 --- a/accelerator/test_methods/a_test_dataset_type_minmax.py +++ b/accelerator/test_methods/a_test_dataset_type_minmax.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify that dataset_type gets .min and .max right. ''' diff --git a/accelerator/test_methods/a_test_dataset_unroundrobin.py b/accelerator/test_methods/a_test_dataset_unroundrobin.py index 01b20218..6a39061c 100644 --- a/accelerator/test_methods/a_test_dataset_unroundrobin.py +++ b/accelerator/test_methods/a_test_dataset_unroundrobin.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test that dataset_unroundrobin produces the correct order. ''' diff --git a/accelerator/test_methods/a_test_dataset_unroundrobin_trigger.py b/accelerator/test_methods/a_test_dataset_unroundrobin_trigger.py index 2794bf6b..d8c98439 100644 --- a/accelerator/test_methods/a_test_dataset_unroundrobin_trigger.py +++ b/accelerator/test_methods/a_test_dataset_unroundrobin_trigger.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test that dataset_unroundrobin with trigger_column produces the correct order and switches slice at the expected point. diff --git a/accelerator/test_methods/a_test_datasetwriter.py b/accelerator/test_methods/a_test_datasetwriter.py index 0fd34d22..fe601c63 100644 --- a/accelerator/test_methods/a_test_datasetwriter.py +++ b/accelerator/test_methods/a_test_datasetwriter.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test DatasetWriter, exercising the different ways to create, pass and populate the dataset. diff --git a/accelerator/test_methods/a_test_datasetwriter_copy.py b/accelerator/test_methods/a_test_datasetwriter_copy.py index 14912d7a..9d46d987 100644 --- a/accelerator/test_methods/a_test_datasetwriter_copy.py +++ b/accelerator/test_methods/a_test_datasetwriter_copy.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test copy_mode in DatasetWriter, and three ways to specify the column types (columns={}, add(n, Datasetcolums), .add(n, (t, none_support)). diff --git a/accelerator/test_methods/a_test_datasetwriter_missing_slices.py b/accelerator/test_methods/a_test_datasetwriter_missing_slices.py index 292b91eb..c3235504 100644 --- a/accelerator/test_methods/a_test_datasetwriter_missing_slices.py +++ b/accelerator/test_methods/a_test_datasetwriter_missing_slices.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test that missing set_slice is an error without allow_missing_slices but not with. diff --git a/accelerator/test_methods/a_test_datasetwriter_parent.py b/accelerator/test_methods/a_test_datasetwriter_parent.py index 45fc1501..a33d9c01 100644 --- a/accelerator/test_methods/a_test_datasetwriter_parent.py +++ b/accelerator/test_methods/a_test_datasetwriter_parent.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Exercise different valid and invalid parent/hashlabel combinations in DatasetWriter. diff --git a/accelerator/test_methods/a_test_datasetwriter_verify.py b/accelerator/test_methods/a_test_datasetwriter_verify.py index dc8f0350..844ee990 100644 --- a/accelerator/test_methods/a_test_datasetwriter_verify.py +++ b/accelerator/test_methods/a_test_datasetwriter_verify.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify that each slice contains the expected data after test_datasetwriter. ''' diff --git a/accelerator/test_methods/a_test_datetime.py b/accelerator/test_methods/a_test_datetime.py index 3d0489a8..f2ecce27 100644 --- a/accelerator/test_methods/a_test_datetime.py +++ b/accelerator/test_methods/a_test_datetime.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test the datetime types in options. ''' diff --git a/accelerator/test_methods/a_test_hashlabel.py b/accelerator/test_methods/a_test_hashlabel.py index 5501cc28..4de35170 100644 --- a/accelerator/test_methods/a_test_hashlabel.py +++ b/accelerator/test_methods/a_test_hashlabel.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test that hashlabel does what it says in both split_write and hashcheck. Then test that rehashing gives the expected result, and that using the diff --git a/accelerator/test_methods/a_test_hashpart.py b/accelerator/test_methods/a_test_hashpart.py index c05246e3..3f340880 100644 --- a/accelerator/test_methods/a_test_hashpart.py +++ b/accelerator/test_methods/a_test_hashpart.py @@ -18,10 +18,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify the dataset_hashpart method with various options. ''' diff --git a/accelerator/test_methods/a_test_jobchain.py b/accelerator/test_methods/a_test_jobchain.py index a1b42dbf..e273c56b 100644 --- a/accelerator/test_methods/a_test_jobchain.py +++ b/accelerator/test_methods/a_test_jobchain.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test Job.chain ''' diff --git a/accelerator/test_methods/a_test_jobwithfile.py b/accelerator/test_methods/a_test_jobwithfile.py index e983ebcb..d090e84f 100644 --- a/accelerator/test_methods/a_test_jobwithfile.py +++ b/accelerator/test_methods/a_test_jobwithfile.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test JobWithFile file loading. Pickle and json, sliced and unsliced. diff --git a/accelerator/test_methods/a_test_json.py b/accelerator/test_methods/a_test_json.py index 653ebda6..fe8ad1ad 100644 --- a/accelerator/test_methods/a_test_json.py +++ b/accelerator/test_methods/a_test_json.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify a few corner cases in the json functions in extras. ''' diff --git a/accelerator/test_methods/a_test_nan.py b/accelerator/test_methods/a_test_nan.py index 86b215bb..6c21c2f1 100644 --- a/accelerator/test_methods/a_test_nan.py +++ b/accelerator/test_methods/a_test_nan.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - import gzip import math import os diff --git a/accelerator/test_methods/a_test_number.py b/accelerator/test_methods/a_test_number.py index b77b1443..99185b25 100644 --- a/accelerator/test_methods/a_test_number.py +++ b/accelerator/test_methods/a_test_number.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - import gzip from random import randint import struct diff --git a/accelerator/test_methods/a_test_optionenum.py b/accelerator/test_methods/a_test_optionenum.py index c95d2d2e..f7fd0091 100644 --- a/accelerator/test_methods/a_test_optionenum.py +++ b/accelerator/test_methods/a_test_optionenum.py @@ -18,10 +18,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test OptionEnum construction and enforcement. ''' diff --git a/accelerator/test_methods/a_test_output.py b/accelerator/test_methods/a_test_output.py index 735bb4a1..97218bbb 100644 --- a/accelerator/test_methods/a_test_output.py +++ b/accelerator/test_methods/a_test_output.py @@ -18,10 +18,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify that the output from methods is captured correctly for all valid combinations of prepare/analysis/synthesis, both in OUTPUT dir and in diff --git a/accelerator/test_methods/a_test_rechain.py b/accelerator/test_methods/a_test_rechain.py index c052ba71..9816dd31 100644 --- a/accelerator/test_methods/a_test_rechain.py +++ b/accelerator/test_methods/a_test_rechain.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test re-using datasets (from test_selfchain) in new chains, and verify that the old chain still works. diff --git a/accelerator/test_methods/a_test_register_file.py b/accelerator/test_methods/a_test_register_file.py index a52ce5e0..f6d35540 100644 --- a/accelerator/test_methods/a_test_register_file.py +++ b/accelerator/test_methods/a_test_register_file.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - from accelerator import subjobs description = r''' diff --git a/accelerator/test_methods/a_test_register_file_auto.py b/accelerator/test_methods/a_test_register_file_auto.py index a6ca4c23..9d1fceb1 100644 --- a/accelerator/test_methods/a_test_register_file_auto.py +++ b/accelerator/test_methods/a_test_register_file_auto.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test that the expected files are registered (and not registered) when using job.open(), job.register_file() and job.register_files(). diff --git a/accelerator/test_methods/a_test_register_file_auto_2.py b/accelerator/test_methods/a_test_register_file_auto_2.py index 9be661ea..1b420c04 100644 --- a/accelerator/test_methods/a_test_register_file_auto_2.py +++ b/accelerator/test_methods/a_test_register_file_auto_2.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - import os description = r''' diff --git a/accelerator/test_methods/a_test_register_file_manual.py b/accelerator/test_methods/a_test_register_file_manual.py index d41ed386..04c83f94 100644 --- a/accelerator/test_methods/a_test_register_file_manual.py +++ b/accelerator/test_methods/a_test_register_file_manual.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - import os description = r''' diff --git a/accelerator/test_methods/a_test_selfchain.py b/accelerator/test_methods/a_test_selfchain.py index d9a1cb70..21fc6cd5 100644 --- a/accelerator/test_methods/a_test_selfchain.py +++ b/accelerator/test_methods/a_test_selfchain.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Tests creating several chained datasets in one job. Exercises DatasetWriter.finish and the chaining logic diff --git a/accelerator/test_methods/a_test_shell_commands.py b/accelerator/test_methods/a_test_shell_commands.py index 1ff4dfa0..328831fd 100644 --- a/accelerator/test_methods/a_test_shell_commands.py +++ b/accelerator/test_methods/a_test_shell_commands.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test all the ax sub-commands at least a little bit. ''' diff --git a/accelerator/test_methods/a_test_shell_config.py b/accelerator/test_methods/a_test_shell_config.py index 9a2525cb..3e16273b 100644 --- a/accelerator/test_methods/a_test_shell_config.py +++ b/accelerator/test_methods/a_test_shell_config.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test the alias and colour config for shell commands. ''' diff --git a/accelerator/test_methods/a_test_shell_data.py b/accelerator/test_methods/a_test_shell_data.py index 8716b4a4..87c9c229 100644 --- a/accelerator/test_methods/a_test_shell_data.py +++ b/accelerator/test_methods/a_test_shell_data.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Create some jobs and datasets to test the shell parser with. diff --git a/accelerator/test_methods/a_test_shell_ds.py b/accelerator/test_methods/a_test_shell_ds.py index c34df48b..c1112b52 100644 --- a/accelerator/test_methods/a_test_shell_ds.py +++ b/accelerator/test_methods/a_test_shell_ds.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test the "ax ds" shell command. Primarily tests the job spec parser. ''' @@ -50,4 +46,3 @@ def synthesis(job): got_ds = res[0] ds = quote(ds) assert ds == got_ds, 'Spec %r should have given %r but gave %r' % (spec, ds, got_ds,) - diff --git a/accelerator/test_methods/a_test_shell_grep.py b/accelerator/test_methods/a_test_shell_grep.py index 58cf79e9..27352cf2 100644 --- a/accelerator/test_methods/a_test_shell_grep.py +++ b/accelerator/test_methods/a_test_shell_grep.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test the "ax grep" shell command. This isn't testing complex regexes, but rather the various output options and data types. diff --git a/accelerator/test_methods/a_test_shell_job.py b/accelerator/test_methods/a_test_shell_job.py index b6ede9f9..a315aa3f 100644 --- a/accelerator/test_methods/a_test_shell_job.py +++ b/accelerator/test_methods/a_test_shell_job.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test the "ax job" shell command. Primarily tests the job spec parser. ''' diff --git a/accelerator/test_methods/a_test_sort_chaining.py b/accelerator/test_methods/a_test_sort_chaining.py index 73ef00c1..83f59eea 100644 --- a/accelerator/test_methods/a_test_sort_chaining.py +++ b/accelerator/test_methods/a_test_sort_chaining.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test dataset_sort as a chain, across a chain and as a chain merging only two datasets of the original chain. diff --git a/accelerator/test_methods/a_test_sort_stability.py b/accelerator/test_methods/a_test_sort_stability.py index 9d79e29b..85c9c5ab 100644 --- a/accelerator/test_methods/a_test_sort_stability.py +++ b/accelerator/test_methods/a_test_sort_stability.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test that dataset_sort sorts stably. diff --git a/accelerator/test_methods/a_test_sort_trigger.py b/accelerator/test_methods/a_test_sort_trigger.py index be24f72c..099c8d22 100644 --- a/accelerator/test_methods/a_test_sort_trigger.py +++ b/accelerator/test_methods/a_test_sort_trigger.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test dataset_sort with trigger_column ''' diff --git a/accelerator/test_methods/a_test_sorting.py b/accelerator/test_methods/a_test_sorting.py index c50eafd3..e832fc21 100644 --- a/accelerator/test_methods/a_test_sorting.py +++ b/accelerator/test_methods/a_test_sorting.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test dataset_sort with various options on a dataset with all types. ''' diff --git a/accelerator/test_methods/a_test_sorting_gendata.py b/accelerator/test_methods/a_test_sorting_gendata.py index cfb25d10..ea8d5b5e 100644 --- a/accelerator/test_methods/a_test_sorting_gendata.py +++ b/accelerator/test_methods/a_test_sorting_gendata.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Generate data for test_sorting. ''' diff --git a/accelerator/test_methods/a_test_status_in_exceptions.py b/accelerator/test_methods/a_test_status_in_exceptions.py index 946f2630..4cffe813 100644 --- a/accelerator/test_methods/a_test_status_in_exceptions.py +++ b/accelerator/test_methods/a_test_status_in_exceptions.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test that the JobError exception contains the correct status stack and line number from dataset iteration. diff --git a/accelerator/test_methods/a_test_subjobs_nesting.py b/accelerator/test_methods/a_test_subjobs_nesting.py index 7be08f91..c746d378 100644 --- a/accelerator/test_methods/a_test_subjobs_nesting.py +++ b/accelerator/test_methods/a_test_subjobs_nesting.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Verify that subjobs are allowed to nest (exactly) five levels. ''' diff --git a/accelerator/test_methods/a_test_subjobs_type.py b/accelerator/test_methods/a_test_subjobs_type.py index 2c8b4d4f..b7810671 100644 --- a/accelerator/test_methods/a_test_subjobs_type.py +++ b/accelerator/test_methods/a_test_subjobs_type.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Type datasets.untyped the same as datasets.typed in a subjob, then verify (in another subjob) the the results are correct. diff --git a/accelerator/test_methods/a_test_summary.py b/accelerator/test_methods/a_test_summary.py index 089f6d6e..0b0b6a2c 100644 --- a/accelerator/test_methods/a_test_summary.py +++ b/accelerator/test_methods/a_test_summary.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Produce a summary that build_tests can put in the result directory. ''' diff --git a/accelerator/test_methods/a_test_urd.py b/accelerator/test_methods/a_test_urd.py index 67319798..3c348908 100644 --- a/accelerator/test_methods/a_test_urd.py +++ b/accelerator/test_methods/a_test_urd.py @@ -17,10 +17,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - description = r''' Test a stand-alone urd for compatibility with old logs and some calls. ''' diff --git a/accelerator/test_methods/build_tests.py b/accelerator/test_methods/build_tests.py index dc3f5e51..5d8f23a1 100644 --- a/accelerator/test_methods/build_tests.py +++ b/accelerator/test_methods/build_tests.py @@ -18,10 +18,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - from accelerator.dataset import Dataset from accelerator.build import JobError from accelerator.compat import monotonic diff --git a/accelerator/test_methods/test_data.py b/accelerator/test_methods/test_data.py index a0bc5870..752c2dc9 100644 --- a/accelerator/test_methods/test_data.py +++ b/accelerator/test_methods/test_data.py @@ -19,10 +19,6 @@ # Test data for use in dataset testing -from __future__ import print_function -from __future__ import division -from __future__ import unicode_literals - from datetime import date, time, datetime from sys import version_info diff --git a/accelerator/unixhttp.py b/accelerator/unixhttp.py index efd393e8..6c8b55a9 100644 --- a/accelerator/unixhttp.py +++ b/accelerator/unixhttp.py @@ -19,9 +19,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - from accelerator.compat import urlopen, Request, URLError, HTTPError from accelerator.extras import json_encode, json_decode from accelerator.error import ServerError, UrdError, UrdPermissionError, UrdConflictError diff --git a/accelerator/urd.py b/accelerator/urd.py index 63be7362..4e2fa685 100644 --- a/accelerator/urd.py +++ b/accelerator/urd.py @@ -19,10 +19,6 @@ # # ############################################################################ -from __future__ import unicode_literals -from __future__ import print_function -from __future__ import division - from glob import glob from collections import defaultdict from bottle import route, request, auth_basic, abort diff --git a/accelerator/workspace.py b/accelerator/workspace.py index 195d5715..d2b354e7 100644 --- a/accelerator/workspace.py +++ b/accelerator/workspace.py @@ -19,9 +19,6 @@ # # ############################################################################ -from __future__ import print_function -from __future__ import division - import os from accelerator.job import Job diff --git a/dsutil/test.py b/dsutil/test.py index e180526d..44e6e87a 100755 --- a/dsutil/test.py +++ b/dsutil/test.py @@ -22,8 +22,6 @@ # Verify general operation and a few corner cases. -from __future__ import division, print_function, unicode_literals - from datetime import datetime, date, time from sys import version_info from itertools import compress diff --git a/setup.py b/setup.py index 74f8f3fa..774dd52d 100755 --- a/setup.py +++ b/setup.py @@ -20,8 +20,6 @@ # # ############################################################################ -from __future__ import print_function - from setuptools import setup, find_packages, Extension from importlib import import_module from os.path import exists From cbfa6396d08434e97c625ffcc0c82e3a1cb3da64 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?= Date: Tue, 19 Aug 2025 16:58:19 +0200 Subject: [PATCH 12/18] Revert "fix ordered DotDicts for python2" This reverts commit 4e7fb2680af15f2f3d3dfe75b49dd3da09364a81. --- accelerator/extras.py | 5 ----- 1 file changed, 5 deletions(-) diff --git a/accelerator/extras.py b/accelerator/extras.py index 30bce23d..41786b0c 100644 --- a/accelerator/extras.py +++ b/accelerator/extras.py @@ -489,11 +489,6 @@ def __getattr__(self, name): raise AttributeError(name) def __setattr__(self, name, value): - # if using the python implementation of OrderedDict (as python2 does) - # this is needed. don't worry about __slots__, it won't apply in that - # case, and __getattr__ is not needed as it falls through automatically. - if name.startswith('_OrderedDict__'): - return OrderedDict.__setattr__(self, name, value) if name[0] == "_": raise AttributeError(name) self[name] = value From a0f58380749f1e8ac047945b5293eae33657e990 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?= Date: Tue, 19 Aug 2025 17:24:20 +0200 Subject: [PATCH 13/18] Migrate old-style "%" formatting of strings to f-strings This has been done automatically using flynt: https://github.com/ikamensh/flynt --- accelerator/board.py | 30 ++--- accelerator/build.py | 48 ++++---- accelerator/colourwrapper.py | 16 +-- accelerator/compat.py | 8 +- accelerator/configfile.py | 32 ++--- accelerator/control.py | 6 +- accelerator/database.py | 6 +- accelerator/dataset.py | 114 +++++++++--------- accelerator/deptree.py | 30 ++--- accelerator/dispatch.py | 6 +- accelerator/dsutil.py | 4 +- accelerator/error.py | 6 +- .../examples/a_example_returninprepanasyn.py | 2 +- .../examples/a_example_writeslicedfile.py | 4 +- accelerator/examples/build_dsexample-chain.py | 6 +- .../examples/build_dsexample-create.py | 2 +- .../examples/build_dsexample-many_ds.py | 2 +- .../examples/build_example-depend_extra.py | 2 +- .../examples/build_example-equiv_hashes.py | 4 +- accelerator/examples/build_example-files.py | 10 +- accelerator/examples/build_example-options.py | 6 +- accelerator/examples/build_tutorial01.py | 4 +- accelerator/examples/build_tutorial02.py | 8 +- accelerator/examples/build_tutorial03.py | 10 +- accelerator/examples/build_tutorial04.py | 2 +- accelerator/examples/build_tutorial05.py | 20 +-- .../examples/build_urdexample-basic.py | 18 +-- .../examples/build_urdexample-many_items.py | 10 +- accelerator/extras.py | 10 +- accelerator/graph.py | 4 +- accelerator/iowrapper.py | 2 +- accelerator/job.py | 14 +-- accelerator/launch.py | 2 +- accelerator/metadata.py | 2 +- accelerator/methods.py | 20 +-- accelerator/runner.py | 30 ++--- accelerator/server.py | 14 +-- accelerator/setupfile.py | 6 +- accelerator/shell/__init__.py | 22 ++-- accelerator/shell/ds.py | 22 ++-- accelerator/shell/gc.py | 4 +- accelerator/shell/grep.py | 22 ++-- accelerator/shell/hist.py | 6 +- accelerator/shell/init.py | 8 +- accelerator/shell/job.py | 18 +-- accelerator/shell/lined.py | 10 +- accelerator/shell/method.py | 10 +- accelerator/shell/parser.py | 34 +++--- accelerator/shell/script.py | 2 +- accelerator/shell/sherlock.py | 8 +- accelerator/shell/status.py | 4 +- accelerator/shell/urd.py | 8 +- accelerator/shell/workdir.py | 2 +- accelerator/standard_methods/a_csvexport.py | 2 +- accelerator/standard_methods/a_csvimport.py | 6 +- .../standard_methods/a_csvimport_zip.py | 4 +- .../standard_methods/a_dataset_checksum.py | 4 +- .../a_dataset_checksum_chain.py | 2 +- .../standard_methods/a_dataset_concat.py | 4 +- .../standard_methods/a_dataset_fanout.py | 8 +- .../standard_methods/a_dataset_type.py | 24 ++-- .../a_dataset_unroundrobin.py | 2 +- .../standard_methods/c_backend_support.py | 4 +- accelerator/standard_methods/dataset_type.py | 4 +- accelerator/statmsg.py | 10 +- accelerator/subjobs.py | 6 +- .../test_methods/a_test_board_metadata.py | 8 +- .../a_test_csvexport_all_coltypes.py | 6 +- .../test_methods/a_test_csvexport_chains.py | 2 +- .../test_methods/a_test_csvexport_naming.py | 2 +- .../test_methods/a_test_csvexport_quoting.py | 4 +- .../a_test_csvexport_separators.py | 2 +- .../a_test_csvimport_corner_cases.py | 22 ++-- .../test_methods/a_test_csvimport_zip.py | 8 +- .../test_methods/a_test_dataset_callbacks.py | 2 +- .../a_test_dataset_column_names.py | 2 +- .../test_methods/a_test_dataset_concat.py | 2 +- .../a_test_dataset_empty_colname.py | 4 +- .../test_methods/a_test_dataset_fanout.py | 12 +- .../a_test_dataset_filter_columns.py | 4 +- .../test_methods/a_test_dataset_merge.py | 6 +- .../test_methods/a_test_dataset_nan.py | 4 +- .../a_test_dataset_parsing_writer.py | 4 +- .../a_test_dataset_rename_columns.py | 4 +- .../test_methods/a_test_dataset_slice.py | 2 +- .../test_methods/a_test_dataset_type_None.py | 2 +- .../a_test_dataset_type_chaining.py | 2 +- .../a_test_dataset_type_corner_cases.py | 42 +++---- .../a_test_dataset_type_hashing.py | 16 +-- .../a_test_dataset_type_minmax.py | 8 +- .../a_test_dataset_unroundrobin.py | 6 +- .../a_test_dataset_unroundrobin_trigger.py | 2 +- .../test_methods/a_test_datasetwriter_copy.py | 4 +- .../a_test_datasetwriter_default.py | 8 +- .../a_test_datasetwriter_parsed.py | 16 +-- accelerator/test_methods/a_test_hashlabel.py | 6 +- accelerator/test_methods/a_test_hashpart.py | 8 +- accelerator/test_methods/a_test_job_save.py | 8 +- .../a_test_job_save_background.py | 12 +- accelerator/test_methods/a_test_json.py | 8 +- accelerator/test_methods/a_test_nan.py | 14 +-- accelerator/test_methods/a_test_number.py | 6 +- accelerator/test_methods/a_test_optionenum.py | 4 +- accelerator/test_methods/a_test_output.py | 10 +- .../test_methods/a_test_output_on_error.py | 2 +- .../test_methods/a_test_register_file.py | 6 +- .../test_methods/a_test_shell_commands.py | 8 +- .../test_methods/a_test_shell_config.py | 6 +- accelerator/test_methods/a_test_shell_ds.py | 2 +- accelerator/test_methods/a_test_shell_grep.py | 8 +- accelerator/test_methods/a_test_shell_job.py | 2 +- .../test_methods/a_test_sort_trigger.py | 10 +- accelerator/test_methods/a_test_sorting.py | 2 +- accelerator/test_methods/a_test_urd.py | 4 +- accelerator/test_methods/build_tests.py | 10 +- accelerator/unixhttp.py | 6 +- accelerator/urd.py | 18 +-- accelerator/workspace.py | 6 +- dsutil/test.py | 18 +-- scripts/templates/a_check.py | 4 +- setup.py | 2 +- 121 files changed, 588 insertions(+), 588 deletions(-) diff --git a/accelerator/board.py b/accelerator/board.py index e7a850b8..e6f34457 100644 --- a/accelerator/board.py +++ b/accelerator/board.py @@ -78,14 +78,14 @@ def ax_repr(o): res = [] if isinstance(o, JobWithFile): link = '/job/' + bottle.html_escape(o.job) - res.append('JobWithFile(job=' % (link,)) + res.append(f'JobWithFile(job=') res.append(ax_repr(o.job)) name = bottle.html_escape(o.name) if o.sliced: name += '.0' - res.append(', name=' % (link, name,)) + res.append(f', name=') res.append(ax_repr(o.name)) - res.append(', sliced=%s, extra=%s' % (ax_repr(o.sliced), ax_repr(o.extra),)) + res.append(f', sliced={ax_repr(o.sliced)}, extra={ax_repr(o.extra)}') res.append(')') elif isinstance(o, (list, tuple)): bra, ket = ('[', ']',) if isinstance(o, list) else ('(', ')',) @@ -112,17 +112,17 @@ def ax_repr(o): def ax_link(v): if isinstance(v, tuple): - return '(%s)' % (', '.join(ax_link(vv) for vv in v),) + return f'({", ".join(ax_link(vv) for vv in v)})' elif isinstance(v, list): - return '[%s]' % (', '.join(ax_link(vv) for vv in v),) + return f'[{", ".join(ax_link(vv) for vv in v)}]' elif v: ev = bottle.html_escape(v) if isinstance(v, Dataset): job = bottle.html_escape(v.job) name = bottle.html_escape(v.name) - return '%s/%s' % (url_quote(v.job), job, url_quote(v), name,) + return f'{job}/{name}' elif isinstance(v, Job): - return '%s' % (url_quote(v), ev,) + return f'{ev}' else: return ev else: @@ -267,7 +267,7 @@ def run(cfg, from_shell=False, development=False): _development = development project = os.path.split(cfg.project_directory)[1] - setproctitle('ax board-server for %s on %s' % (project, cfg.board_listen,)) + setproctitle(f'ax board-server for {project} on {cfg.board_listen}') # The default path filter (i.e. ) does not match newlines, # but we want it to do so (e.g. in case someone names a dataset with one). @@ -368,7 +368,7 @@ def static_file(filename, root, job=None): if not ranges: return bottle.HTTPError(416, "Requested Range Not Satisfiable") offset, end = ranges[0] - headers['Content-Range'] = 'bytes %d-%d/%d' % (offset, end-1, clen) + headers['Content-Range'] = f'bytes {offset}-{end-1}/{clen}' headers['Content-Length'] = str(end-offset) if body: body = file_parts_iter(file_parts, clen, body, offset, end) @@ -477,7 +477,7 @@ def results(path=''): job = None return static_file(path, root=cfg.result_directory, job=job) else: - return {'missing': 'result directory %r missing' % (cfg.result_directory,)} + return {'missing': f'result directory {cfg.result_directory!r} missing'} @bottle.get('/status') @view('status') @@ -488,7 +488,7 @@ def status(): return 'idle' else: t, msg, _ = status.current - return '%s (%s)' % (msg, fmttime(status.report_t - t, short=True),) + return f'{msg} ({fmttime(status.report_t - t, short=True)})' else: status.tree = list(fix_stacks(status.pop('status_stacks', ()), status.report_t)) return status @@ -517,7 +517,7 @@ def job_method(jobid, name=None): accept = get_best_accept('text/plain', 'text/html') if accept == 'text/html': try: - fmter = HtmlFormatter(full=True, encoding='utf-8', linenos='table', title='%s from %s' % (info.name, job,)) + fmter = HtmlFormatter(full=True, encoding='utf-8', linenos='table', title=f'{info.name} from {job}') code = highlight(code, PythonLexer(), fmter) bottle.response.content_type = 'text/html; charset=UTF-8' except Exception: @@ -568,7 +568,7 @@ def job(jobid): try: v, lr = job.load('link_result.pickle') if v == 0: - results = '[%s]' % ', '.join(v for _, v in lr) + results = f'[{", ".join(v for _, v in lr)}]' except FileNotFoundError: pass else: @@ -666,7 +666,7 @@ def methods(): def method(name): methods = call_s('methods') if name not in methods: - return bottle.HTTPError(404, 'Method %s not found' % (name,)) + return bottle.HTTPError(404, f'Method {name} not found') return dict(name=name, data=methods[name], cfg=cfg) @bottle.get('/urd') @@ -700,7 +700,7 @@ def urditem(user, build, ts): bjob = name2job(cfg, d['build_job']) v, lr = bjob.load('link_result.pickle') if v == 0: - results = '[%s]' % (', '.join(v for k, v in lr if k == key),) + results = f"[{', '.join((v for k, v in lr if k == key))}]" if results == '[]': results = None except (FileNotFoundError, NoSuchJobError): diff --git a/accelerator/build.py b/accelerator/build.py index c1d1b1d1..841a06e4 100644 --- a/accelerator/build.py +++ b/accelerator/build.py @@ -158,7 +158,7 @@ def wait(self, ignore_old_errors=False): current = (now - t0, self.job_method, 0,) if self.verbose == 'dots': if waited % 60 == 0: - sys.stdout.write('[%d]\n ' % (now - t0,)) + sys.stdout.write(f'[{now - t0}]\n ') else: sys.stdout.write('.') elif self.verbose == 'log': @@ -175,7 +175,7 @@ def wait(self, ignore_old_errors=False): if self.verbose == 'dots': print('(%d)]' % (last_time,)) elif self.verbose: - print('\r\033[K %s' % (fmttime(last_time),)) + print(f'\r\x1b[K {fmttime(last_time)}') def jobid(self, method): """ @@ -189,7 +189,7 @@ def _server_idle(self, timeout=0, ignore_errors=False): path = ['status'] if self.verbose: path.append('full') - path.append('?subjob_cookie=%s&timeout=%s' % (self.subjob_cookie or '', timeout,)) + path.append(f"?subjob_cookie={self.subjob_cookie or ''}&timeout={timeout}") resp = self._url_json(*path) if 'last_error_time' in resp and resp.last_error_time != self.last_error_time: self.last_error_time = resp.last_error_time @@ -223,7 +223,7 @@ def _printlist(self, returndict): link_msg = Job(item.link).path else: link_msg = item.link - msg = ' - %-35s %-5s %s' % (method, make_msg, link_msg,) + msg = f' - {method:35} {make_msg:5} {link_msg}' if item.make != True and 'total_time' in item: msg = msg + ' ' + fmttime(item.total_time).rjust(78 - len(msg)) print(msg) @@ -251,7 +251,7 @@ def list_workdirs(self): def call_method(self, method, options={}, datasets={}, jobs={}, record_as=None, why_build=False, force_build=False, caption=None, workdir=None, concurrency=None, **kw): if method not in self._method_info: - raise BuildError('Unknown method %s' % (method,)) + raise BuildError(f'Unknown method {method}') info = self._method_info[method] params = dict(options=dict(options), datasets=dict(datasets), jobs=dict(jobs)) argmap = defaultdict(list) @@ -260,9 +260,9 @@ def call_method(self, method, options={}, datasets={}, jobs={}, record_as=None, argmap[n].append(thing) for k, v in kw.items(): if k not in argmap: - raise BuildError('Keyword %s not in options/datasets/jobs for method %s' % (k, method,)) + raise BuildError(f'Keyword {k} not in options/datasets/jobs for method {method}') if len(argmap[k]) != 1: - raise BuildError('Keyword %s has several targets on method %s: %r' % (k, method, argmap[k],)) + raise BuildError(f'Keyword {k} has several targets on method {method}: {argmap[k]!r}') params[argmap[k][0]][k] = v jid, res = self._submit(method, caption=caption, why_build=why_build, force_build=force_build, workdir=workdir, concurrency=concurrency, **params) if why_build: # specified by caller @@ -422,7 +422,7 @@ def _tsfix(ts): if ts is None: return None from accelerator.urd import TimeStamp - errmsg = 'Specify timestamps as strings, ints, datetimes or a list of those, not %r' % (ts,) + errmsg = f'Specify timestamps as strings, ints, datetimes or a list of those, not {ts!r}' assert ts or ts == 0, errmsg if isinstance(ts, str_types) and ts[0] in '<>': if ts.startswith('<=') or ts.startswith('>='): @@ -453,14 +453,14 @@ class Urd(object): def __init__(self, a, info, user, password, horizon=None, default_workdir=None): self._a = a if info.urd: - assert '://' in str(info.urd), 'Bad urd URL: %s' % (info.urd,) + assert '://' in str(info.urd), f'Bad urd URL: {info.urd}' self._url = info.urd or '' self._user = user self.info = info self.flags = set(a.flags) self.horizon = horizon self.default_workdir = default_workdir - auth = '%s:%s' % (user, password,) + auth = f'{user}:{password}' auth = b64encode(auth.encode('utf-8')).decode('ascii') self._headers = {'Content-Type': 'application/json', 'Authorization': 'Basic ' + auth} self._auth_tested = False @@ -487,7 +487,7 @@ def joblist(self): def _path(self, path): if '/' not in path: - path = '%s/%s' % (self._user, path,) + path = f'{self._user}/{path}' return path def _call(self, url, data=None, fmt=_urd_typeify): @@ -535,7 +535,7 @@ def peek_first(self, path): def since(self, path, timestamp): path = self._path(path) - url = '%s/%s/since/%s' % (self._url, path, _tsfix(timestamp),) + url = f'{self._url}/{path}/since/{_tsfix(timestamp)}' return self._call(url, fmt=json.loads) def list(self): @@ -545,7 +545,7 @@ def list(self): def _test_auth(self): if not self._auth_tested: try: - self._call('%s/test/%s' % (self._url, self._user,), True) + self._call(f'{self._url}/test/{self._user}', True) except UrdPermissionError: return False self._auth_tested = True @@ -560,7 +560,7 @@ def _move_link_result(self, key=None): self._link_result_current = [] def begin(self, path, timestamp=None, caption=None, update=False): - assert not self._current, 'Tried to begin %s while running %s' % (path, self._current,) + assert not self._current, f'Tried to begin {path} while running {self._current}' if not self._test_auth(): raise BuildError('Urd says permission denied, did you forget to set URD_AUTH?') self._move_link_result() @@ -578,9 +578,9 @@ def abort(self): def finish(self, path, timestamp=None, caption=None): path = self._path(path) - assert self._current, 'Tried to finish %s with nothing running' % (path,) - assert path == self._current, 'Tried to finish %s while running %s' % (path, self._current,) - assert self.joblist, 'Tried to finish %s without building any jobs' % (path,) + assert self._current, f'Tried to finish {path} with nothing running' + assert path == self._current, f'Tried to finish {path} while running {self._current}' + assert self.joblist, f'Tried to finish {path} without building any jobs' user, build = path.split('/') self._current = None caption = caption or self._current_caption or '' @@ -588,7 +588,7 @@ def finish(self, path, timestamp=None, caption=None): timestamp = self._current_timestamp else: timestamp = _tsfix(timestamp) - assert timestamp, 'No timestamp specified in begin or finish for %s' % (path,) + assert timestamp, f'No timestamp specified in begin or finish for {path}' self._move_link_result(path + '/' + timestamp) data = DotDict( user=user, @@ -605,7 +605,7 @@ def finish(self, path, timestamp=None, caption=None): return self._call(url, data) def truncate(self, path, timestamp): - url = '%s/truncate/%s/%s' % (self._url, self._path(path), _tsfix(timestamp),) + url = f'{self._url}/truncate/{self._path(path)}/{_tsfix(timestamp)}' return self._call(url, '') def set_workdir(self, workdir): @@ -688,7 +688,7 @@ def find_automata(a, script): package = [cand] break else: - raise BuildError('No method directory found for %r in %r' % (package, all_packages)) + raise BuildError(f'No method directory found for {package!r} in {all_packages!r}') else: package = all_packages if not script.startswith('build'): @@ -724,7 +724,7 @@ def prepare_for_run(options, cfg): user = os.environ.get('USER') if not user: user = 'NO-USER' - print("No $URD_AUTH or $USER in environment, using %r" % (user,), file=sys.stderr) + print(f"No $URD_AUTH or $USER in environment, using {user!r}", file=sys.stderr) password = '' info = a.info() urd = Urd(a, info, user, password, options.horizon, options.workdir) @@ -748,7 +748,7 @@ def run_automata(urd, options, cfg, module_ref, main_args): if 'error' in job: print(job.error, file=sys.stderr) return 1 - print('%s running as job %s' % (module_ref.__name__, job.jobid,)) + print(f'{module_ref.__name__} running as job {job.jobid}') setup = setupfile.generate(caption='build script', method=module_ref.__name__, input_directory=cfg.input_directory) setup.starttime = time.time() setup.is_build = True @@ -839,7 +839,7 @@ def run_automata(urd, options, cfg, module_ref, main_args): ts = str(ts).replace(' ', 'T') urd.begin('__auto__', ts) urd._a.joblist = urd.joblist_all # fake it - setup.options['urd-list'] = '%s/%s' % (urd._current, ts) + setup.options['urd-list'] = f'{urd._current}/{ts}' try: urd.finish('__auto__') except UrdError as e: @@ -903,7 +903,7 @@ def main(argv, cfg): method, v = v.split('=', 1) concurrency_map[method] = int(v) except ValueError: - raise BuildError('Bad concurrency spec %r' % (v,)) + raise BuildError(f'Bad concurrency spec {v!r}') options.concurrency_map = concurrency_map urd, modules = prepare_for_run(options, cfg) diff --git a/accelerator/colourwrapper.py b/accelerator/colourwrapper.py index bd46a35e..532edd6c 100644 --- a/accelerator/colourwrapper.py +++ b/accelerator/colourwrapper.py @@ -94,7 +94,7 @@ def __init__(self): self._all['DEFAULTBG'] = '49' for k in self._all: setattr(self, k.lower(), partial(self._single, k)) - self._on = {k: '\x1b[%sm' % (v,) for k, v in self._all.items()} + self._on = {k: f'\x1b[{v}m' for k, v in self._all.items()} self._on['RESET'] = '\x1b[m' self._all['RESET'] = '' self._off = dict.fromkeys(self._on, '') @@ -165,7 +165,7 @@ def _literal_split(self, pieces): def pre_post(self, *attrs, **kw): bad_kw = set(kw) - {'force', 'reset'} if bad_kw: - raise TypeError('Unknown keywords %r' % (bad_kw,)) + raise TypeError(f'Unknown keywords {bad_kw!r}') if not attrs: raise TypeError('specify at least one attr') if (self.enabled or kw.get('force')): @@ -178,16 +178,16 @@ def pre_post(self, *attrs, **kw): a_it = self._expand_names(attrs) for a_src, a in a_it: if not a: - raise ColourError('%r expanded to nothing' % (a_src,)) + raise ColourError(f'{a_src!r} expanded to nothing') if a.startswith('>'): - raise ColourError('A >post needs a preceding 
post needs a preceding 
') or a_src != a_post_src:
-						raise ColourError('A 
post (expanded %r from %r)' % (a, a_src,))
+						raise ColourError(f'A 
post (expanded {a!r} from {a_src!r})')
 					literal_post += a_post[1:]
 					pre.append(a)
 					continue
@@ -219,12 +219,12 @@ def pre_post(self, *attrs, **kw):
 								raise ValueError()
 							part = (prefix, '5', str(idx))
 					except (ValueError, AssertionError):
-						raise ColourError('Bad colour spec %r (from %r)' % (a, a_src,))
+						raise ColourError(f'Bad colour spec {a!r} (from {a_src!r})')
 					pre.append(':'.join(part))
 					post.add(default)
 				else:
 					if want not in self._all:
-						raise ColourError('Unknown colour/attr %r (from %r)' % (a, a_src,))
+						raise ColourError(f'Unknown colour/attr {a!r} (from {a_src!r})')
 					pre.append(self._all[want])
 					post.add(self._all.get('NOT' + want, default))
 			pre = ''.join(self._literal_split(pre))
@@ -243,7 +243,7 @@ def __call__(self, value, *attrs, **kw):
 		pre, post = self.pre_post(*attrs, **kw)
 		if isinstance(value, bytes):
 			return b'%s%s%s' % (pre.encode('utf-8'), value, post.encode('utf-8'),)
-		return '%s%s%s' % (pre, value, post,)
+		return f'{pre}{value}{post}'
 
 colour = Colour()
 colour.configure_from_environ()
diff --git a/accelerator/compat.py b/accelerator/compat.py
index 826ffb1d..86b7872b 100644
--- a/accelerator/compat.py
+++ b/accelerator/compat.py
@@ -83,18 +83,18 @@ def url_quote_more(s):
 
 def fmt_num(num):
 	if isinstance(num, float):
-		return '{:_.6g}'.format(num)
+		return f'{num:_.6g}'
 	else:
-		return '{:_}'.format(num)
+		return f'{num:_}'
 
 # This is used in the method launcher to set different titles for each
 # phase/slice. You can use it in the method to override that if you want.
 def setproctitle(title):
 	from accelerator import g
 	if hasattr(g, 'params'):
-		title = '%s %s (%s)' % (g.job, uni(title), g.params.method,)
+		title = f'{g.job} {uni(title)} ({g.params.method})'
 	elif hasattr(g, 'job'):
-		title = '%s %s' % (g.job, uni(title),)
+		title = f'{g.job} {uni(title)}'
 	else:
 		title = uni(title)
 	_setproctitle(title)
diff --git a/accelerator/configfile.py b/accelerator/configfile.py
index 10f7ad35..84dab430 100644
--- a/accelerator/configfile.py
+++ b/accelerator/configfile.py
@@ -83,7 +83,7 @@ class _E(Exception):
 	def parse_package(val):
 		if len(val) == 2:
 			if val[1] != 'auto-discover':
-				raise _E('Either no option or "auto-discover" for package %r.' % (val[0],))
+				raise _E(f'Either no option or "auto-discover" for package {val[0]!r}.')
 			else:
 				return (val[0], True)
 		return (val[0], False)
@@ -95,7 +95,7 @@ def check_interpreter(val):
 		if val[0] == 'DEFAULT':
 			raise _E("Don't override DEFAULT interpreter")
 		if not os.path.isfile(val[1]):
-			raise _E('%r does not exist' % (val,))
+			raise _E(f'{val!r} does not exist')
 	def check_workdirs(val):
 		name, path = val
 		if val in cfg['workdirs']:
@@ -107,11 +107,11 @@ def check_workdirs(val):
 			# in your config, and have it still work for the foo and bar users.
 			return
 		if name in (v[0] for v in cfg['workdirs']):
-			raise _E('Workdir %s redefined' % (name,))
+			raise _E(f'Workdir {name} redefined')
 		if path in (v[1] for v in cfg['workdirs']):
-			raise _E('Workdir path %r re-used' % (path,))
+			raise _E(f'Workdir path {path!r} re-used')
 		if project_directory == path or project_directory.startswith(path + '/'):
-			raise _E('project directory (%r) is under workdir %s (%r)' % (project_directory, name, path))
+			raise _E(f'project directory ({project_directory!r}) is under workdir {name} ({path!r})')
 
 	def resolve_urd(val):
 		orig_val = val
@@ -122,7 +122,7 @@ def resolve_urd(val):
 			else:
 				val = [val[1]]
 		if len(val) != 1:
-			raise _E("urd takes 1 or 2 values (expected %s, got %r)" % (' '.join(parsers['urd'][0]), orig_val))
+			raise _E(f"urd takes 1 or 2 values (expected {' '.join(parsers['urd'][0])}, got {orig_val!r})")
 		return is_local, resolve_listen(val[0])
 
 	parsers = {
@@ -155,7 +155,7 @@ def parse(handle):
 					raise _E('Expected a ":"')
 				key, val = line.split(':', 1)
 				if key not in known:
-					raise _E('Unknown key %r' % (key,))
+					raise _E(f'Unknown key {key!r}')
 			else:
 				if not key:
 					raise _E('First line indented')
@@ -166,7 +166,7 @@ def parse(handle):
 	def just_project_directory(key, val):
 		if key == 'project directory':
 			if len(val) != 1:
-				raise _E("%s takes a single value path (maybe you meant to quote it?)" % (key,))
+				raise _E(f"{key} takes a single value path (maybe you meant to quote it?)")
 			project_directory[0] = val[0]
 	def everything(key, val):
 		if key in parsers:
@@ -179,23 +179,23 @@ def everything(key, val):
 				want_count_str = str(want_count[0])
 			if len(val) not in want_count:
 				if len(args) == 1:
-					raise _E("%s takes a single value %s (maybe you meant to quote it?)" % (key, args[0]))
+					raise _E(f"{key} takes a single value {args[0]} (maybe you meant to quote it?)")
 				else:
-					raise _E("%s takes %s values (expected %s, got %r)" % (key, want_count_str, ' '.join(args), val))
+					raise _E(f"{key} takes {want_count_str} values (expected {' '.join(args)}, got {val!r})")
 			if len(args) == 1:
 				val = val[0]
 			val = p(val)
 		elif len(val) == 1:
 			val = val[0]
 		else:
-			raise _E("%s takes a single value (maybe you meant to quote it?)" % (key,))
+			raise _E(f"{key} takes a single value (maybe you meant to quote it?)")
 		if key in checkers:
 			checkers[key](val)
 		if key in multivalued:
 			cfg[key].append(val)
 		else:
 			if key in cfg:
-				raise _E("%r doesn't take multiple values" % (key,))
+				raise _E(f"{key!r} doesn't take multiple values")
 			cfg[key] = val
 
 	try:
@@ -212,7 +212,7 @@ def everything(key, val):
 			if not cfg[req]:
 				missing.add(req)
 		if missing:
-			raise _E('Missing required keys %r' % (missing,))
+			raise _E(f'Missing required keys {missing!r}')
 
 		# Reformat result a bit so the new format doesn't require code changes all over the place.
 		rename = {
@@ -237,10 +237,10 @@ def everything(key, val):
 			res.result_directory = fixpath('')
 		res.workdirs = dict(res.workdirs)
 		if res.target_workdir not in res.workdirs:
-			raise _E('target workdir %r not in defined workdirs %r' % (res.target_workdir, set(res.workdirs),))
+			raise _E(f'target workdir {res.target_workdir!r} not in defined workdirs {set(res.workdirs)!r}')
 		res.interpreters = dict(res.interpreters)
 		for exe in res.interpreters.values():
-			assert os.path.exists(exe), 'Executable %r does not exist.' % (exe,)
+			assert os.path.exists(exe), f'Executable {exe!r} does not exist.'
 		res.listen, res.url = fixup_listen(res.project_directory, res.listen)
 		if res.get('urd'):
 			res.urd_local, listen = res.urd
@@ -251,7 +251,7 @@ def everything(key, val):
 		res.method_directories = dict(res.method_directories)
 	except _E as e:
 		if lineno[0] is None:
-			prefix = 'Error in %s:\n' % (filename,)
+			prefix = f'Error in {filename}:\n'
 		else:
 			prefix = 'Error on line %d of %s:\n' % (lineno[0], filename,)
 		raise UserError(prefix + e.args[0])
diff --git a/accelerator/control.py b/accelerator/control.py
index f9f0a8bf..7fd3cd37 100644
--- a/accelerator/control.py
+++ b/accelerator/control.py
@@ -73,7 +73,7 @@ def __init__(self, config, options, server_url):
 	def _update_methods(self, _override_py_exe=None):
 		print('Update methods')
 		if _override_py_exe:
-			assert exists(_override_py_exe), 'Executable %r does not exist.' % (_override_py_exe,)
+			assert exists(_override_py_exe), f'Executable {_override_py_exe!r} does not exist.'
 			config = DotDict(self.config)
 			# Doesn't override the automatic version.number names.
 			config.interpreters = {
@@ -163,7 +163,7 @@ def update(name):
 				t_l.append(t)
 			for t in t_l:
 				t.join()
-			assert not failed, "%s failed to update" % (', '.join(failed),)
+			assert not failed, f"{', '.join(failed)} failed to update"
 		finally:
 			pool.close()
 		self.DataBase._update_finish(self.Methods.hash)
@@ -173,7 +173,7 @@ def initialise_jobs(self, setup, workdir=None):
 		""" Update database, check deps, create jobids. """
 		ws = workdir or self.target_workdir
 		if ws not in self.workspaces:
-			raise BuildError("Workdir %s does not exist" % (ws,))
+			raise BuildError(f"Workdir {ws} does not exist")
 		return dependency.initialise_jobs(
 			setup,
 			self.workspaces[ws],
diff --git a/accelerator/database.py b/accelerator/database.py
index 089c7424..4de204b2 100644
--- a/accelerator/database.py
+++ b/accelerator/database.py
@@ -103,7 +103,7 @@ def add_single_jobid(self, jobid):
 	def _update_workspace(self, WorkSpace, pool, verbose=False):
 		"""Insert all items in WorkSpace in database (call update_finish too)"""
 		if verbose:
-			print("DATABASE:  update for \"%s\"" % WorkSpace.name)
+			print(f"DATABASE:  update for \"{WorkSpace.name}\"")
 		filesystem_jobids = WorkSpace.valid_jobids
 		self._fsjid.update(filesystem_jobids)
 		if verbose > 1:
@@ -113,7 +113,7 @@ def _update_workspace(self, WorkSpace, pool, verbose=False):
 		if new_jobids:
 			_paramsdict.update(pool.imap_unordered(_get_params, new_jobids, chunksize=64))
 		if verbose:
-			print("DATABASE:  Database \"%s\" contains %d potential items" % (WorkSpace.name, len(filesystem_jobids), ))
+			print(f"DATABASE:  Database \"{WorkSpace.name}\" contains {len(filesystem_jobids)} potential items")
 
 	def _update_finish(self, dict_of_hashes, verbose=False):
 		"""Filters in-use database on valid hashes.
@@ -172,7 +172,7 @@ def _update_finish(self, dict_of_hashes, verbose=False):
 			l.sort(key=lambda jid: _paramsdict[jid][0].starttime)
 		if verbose:
 			if discarded_due_to_hash_list:
-				print("DATABASE:  discarding due to unknown hash: %s" % ', '.join(discarded_due_to_hash_list))
+				print(f"DATABASE:  discarding due to unknown hash: {', '.join(discarded_due_to_hash_list)}")
 			print("DATABASE:  Full database contains %d items" % (sum(len(v) for v in itervalues(self.db_by_method)),))
 
 	def match_complex(self, reqlist):
diff --git a/accelerator/dataset.py b/accelerator/dataset.py
index f044fe4d..4d2edeab 100644
--- a/accelerator/dataset.py
+++ b/accelerator/dataset.py
@@ -100,7 +100,7 @@ def _dsid(t):
 		jid, name = t
 		if not jid:
 			return None
-		t = '%s/%s' % (jid.split('/')[0], uni(name) or 'default')
+		t = f"{jid.split('/')[0]}/{uni(name) or 'default'}"
 	elif isinstance(t, DatasetWriter):
 		t = t.ds_name
 	if '/' not in t:
@@ -148,17 +148,17 @@ def _ds_load(obj):
 			try:
 				dslist = obj.job.datasets
 				if not dslist:
-					extra = ' (%s contains no datasets)' % (obj.job,)
+					extra = f' ({obj.job} contains no datasets)'
 				elif len(dslist) == 1:
-					extra = ' (did you mean %s?)' % (dslist[0].quoted,)
+					extra = f' (did you mean {dslist[0].quoted}?)'
 				elif len(dslist) < 5:
-					extra = ' (did you mean one of [%s]?)' % (', '.join(ds.quoted for ds in dslist),)
+					extra = f" (did you mean one of [{', '.join((ds.quoted for ds in dslist))}]?)"
 				else:
-					extra = ' (job contains %d other datasets, use "ax ds -l %s" to list them)' % (len(dslist), obj.job,)
+					extra = f' (job contains {len(dslist)} other datasets, use "ax ds -l {obj.job}" to list them)'
 			except Exception:
 				# We don't want to accidentally give an unrelated exception
 				pass
-			raise NoSuchDatasetError('Dataset %s does not exist%s' % (obj.quoted, extra,))
+			raise NoSuchDatasetError(f'Dataset {obj.quoted} does not exist{extra}')
 		_ds_cache[n] = blob.load(fn)
 		_ds_cache.update(_ds_cache[n].get('cache', ()))
 	return _ds_cache[n]
@@ -169,7 +169,7 @@ def _namechk(name):
 _dummy_iter = iter(())
 
 _dir_name_blacklist = list(range(32)) + [37, 47] # unprintable and '%/'
-_dir_name_blacklist = {chr(c): '\\x%02x' % (c,) for c in _dir_name_blacklist}
+_dir_name_blacklist = {chr(c): f'\\x{c:02x}' for c in _dir_name_blacklist}
 _dir_name_blacklist['\\'] = '\\\\' # make sure names can't collide
 
 def _fs_name(name):
@@ -222,10 +222,10 @@ def __new__(cls, jobid, name=None):
 		if name == 'default':
 			fullname = job
 		else:
-			fullname = '%s/%s' % (job, name,)
+			fullname = f'{job}/{name}'
 		obj = str.__new__(cls, fullname)
 		obj.name = name
-		obj.quoted = quote('%s/%s' % (job, name,))
+		obj.quoted = quote(f'{job}/{name}')
 		obj._job_version = 4 # hopefully
 		obj.fs_name = _fs_name(obj.name)
 		if jobid is _new_dataset_marker:
@@ -249,7 +249,7 @@ def __new__(cls, jobid, name=None):
 					obj.fs_name = obj.name
 			obj._data = DotDict(_ds_load(obj))
 			if obj._data.version[0] != 3:
-				raise DatasetError("%s/%s: Unsupported dataset pickle version %r" % (jobid, name, obj._data.version,))
+				raise DatasetError(f"{jobid}/{name}: Unsupported dataset pickle version {obj._data.version!r}")
 			obj._data.columns = dict(obj._data.columns)
 		obj._cache = {}
 		return obj
@@ -326,7 +326,7 @@ def link_to_here(self, name='default', column_filter=None, rename=None, override
 		You can change the filename too, or clear it by setting ''.
 		"""
 		if name in _datasetwriters or os.path.exists(_fs_name(name) + '.p'):
-			raise DatasetUsageError('Duplicate dataset name "%s"' % (name,))
+			raise DatasetUsageError(f'Duplicate dataset name "{name}"')
 		d = Dataset(self)
 		if rename:
 			renamed = {}
@@ -334,12 +334,12 @@ def link_to_here(self, name='default', column_filter=None, rename=None, override
 			rename_discarded = set()
 			for k, v in rename.items():
 				if k not in d._data.columns:
-					raise DatasetUsageError("Renamed column %r not in dataset" % (k,))
+					raise DatasetUsageError(f"Renamed column {k!r} not in dataset")
 				if v is None:
 					rename_discarded.add(k)
 					continue
 				if v in renamed_src:
-					raise DatasetUsageError("Both %r and %r renamed to %r" % (k, renamed_src[v], v,))
+					raise DatasetUsageError(f"Both {k!r} and {renamed_src[v]!r} renamed to {v!r}")
 				renamed[v] = d._data.columns.pop(k)
 				renamed_src[v] = k
 			d._data.columns.update(renamed)
@@ -359,7 +359,7 @@ def link_to_here(self, name='default', column_filter=None, rename=None, override
 			filtered_columns = {k: v for k, v in d._data.columns.items() if k in column_filter}
 			left_over = column_filter - set(filtered_columns)
 			if left_over:
-				raise DatasetUsageError("Columns in filter not available in dataset: %r" % (left_over,))
+				raise DatasetUsageError(f"Columns in filter not available in dataset: {left_over!r}")
 			if not filtered_columns:
 				raise DatasetUsageError("Filter produced no desired columns.")
 			d._data.columns = filtered_columns
@@ -371,7 +371,7 @@ def link_to_here(self, name='default', column_filter=None, rename=None, override
 				Dataset(override_previous)
 			d._data.previous = override_previous
 			d._update_caches()
-		d._data.parent = '%s/%s' % (d.job, d.name,)
+		d._data.parent = f'{d.job}/{d.name}'
 		if filename is not None:
 			d._data.filename = filename or None
 		d.job = job
@@ -397,9 +397,9 @@ def merge(self, other, name='default', previous=None, allow_unrelated=False):
 		else:
 			previous = None
 		if self == other:
-			raise DatasetUsageError("Can't merge with myself (%s)" % (other.quoted,))
+			raise DatasetUsageError(f"Can't merge with myself ({other.quoted})")
 		if self.lines != other.lines:
-			raise DatasetUsageError("%s and %s don't have the same line counts" % (self.quoted, other.quoted,))
+			raise DatasetUsageError(f"{self.quoted} and {other.quoted} don't have the same line counts")
 		if other.hashlabel is not None:
 			new_ds._data.hashlabel = other.hashlabel
 		elif self.hashlabel in other.columns:
@@ -418,7 +418,7 @@ def parents(ds, tips):
 				return tips
 			related = parents(self, set()) & parents(other, set())
 			if not related:
-				raise DatasetUsageError("%s and %s have no common ancenstors, set allow_unrelated to allow this" % (self.quoted, other.quoted,))
+				raise DatasetUsageError(f"{self.quoted} and {other.quoted} have no common ancenstors, set allow_unrelated to allow this")
 		new_ds.job = job
 		new_ds.name = name
 		new_ds.fs_name = _fs_name(name)
@@ -438,7 +438,7 @@ def _column_iterator(self, sliceno, col, _type=None, _line_report=None, **kw):
 		if not _type:
 			_type = dc.type
 		if _type not in _type2iter:
-			msg = 'Unsupported column type %r on %r in %s' % (_type, col, self.quoted,)
+			msg = f'Unsupported column type {_type!r} on {col!r} in {self.quoted}'
 			if _type.startswith('bits'):
 				msg += ". If you need to use this column, please install the 2022.8.4.dev1 release and use the dataset_unbits methods to convert it."
 			raise DatasetError(msg)
@@ -473,7 +473,7 @@ def _iterator(self, sliceno, columns=None, copy_mode=False, _line_report=None):
 			else:
 				not_found.append(col)
 		if not_found:
-			raise DatasetError("Columns %r not found in %s/%s" % (not_found, self.job, self.name,))
+			raise DatasetError(f"Columns {not_found!r} not found in {self.job}/{self.name}")
 		return res
 
 	def _hashfilter(self, sliceno, hashlabel, it):
@@ -618,7 +618,7 @@ def iterate_list(sliceno, columns, datasets, range=None, sloppy_range=False, has
 			need_types = {col: datasets[0].columns[col].type for col in columns}
 			for d in datasets:
 				for col, t in need_types.items():
-					assert d.columns[col].type == t, "%s column %s has type %s, not %s" % (d, col, d.columns[col].type, t,)
+					assert d.columns[col].type == t, f"{d} column {col} has type {d.columns[col].type}, not {t}"
 		to_iter = []
 		if range:
 			if len(range) != 1:
@@ -659,7 +659,7 @@ def iterate_list(sliceno, columns, datasets, range=None, sloppy_range=False, has
 				return iter(())
 			if slice.stop is not None:
 				if slice.stop < slice.start:
-					raise DatasetUsageError("Wanted %r, but start is bigger than stop" % (slice,))
+					raise DatasetUsageError(f"Wanted {slice!r}, but start is bigger than stop")
 				if slice.start == slice.stop:
 					return iter(())
 			def adj_slice(lines):
@@ -694,9 +694,9 @@ def adj_slice(lines):
 					continue
 			if hashlabel is not None and d.hashlabel != hashlabel:
 				if not rehash:
-					raise DatasetUsageError("%s has hashlabel %r, not %r" % (d, d.hashlabel, hashlabel,))
+					raise DatasetUsageError(f"{d} has hashlabel {d.hashlabel!r}, not {hashlabel!r}")
 				if hashlabel not in d.columns:
-					raise DatasetUsageError("Can't rehash %s on non-existant column %r" % (d, hashlabel,))
+					raise DatasetUsageError(f"Can't rehash {d} on non-existant column {hashlabel!r}")
 				rehash_on = hashlabel
 			else:
 				rehash_on = None
@@ -784,7 +784,7 @@ def _resolve_filters(columns, filters, want_tuple):
 			# Add another lambda to put all fN into local variables.
 			# (This is faster than putting them in "locals", you get
 			# LOAD_DEREF instead of LOAD_GLOBAL.)
-			f = 'lambda %s: %s' % (', '.join(arg_n), f)
+			f = f"lambda {', '.join(arg_n)}: {f}"
 			return eval(f, {}, {})(*arg_v)
 		else:
 			return filters
@@ -813,13 +813,13 @@ def _iterstatus(status_reporting, to_iter):
 		def fmt_dsname(d, sliceno, rehash):
 			if rehash is not None:
 				sliceno = 'REHASH'
-			return '%s:%s' % (d.quoted, sliceno)
+			return f'{d.quoted}:{sliceno}'
 		if len(to_iter) == 1:
 			msg_head = 'Iterating ' + fmt_dsname(*to_iter[0])
 			def update_status(ix, d, sliceno, rehash):
 				pass
 		else:
-			msg_head = 'Iterating %s to %s' % (fmt_dsname(*to_iter[0]), fmt_dsname(*to_iter[-1]),)
+			msg_head = f'Iterating {fmt_dsname(*to_iter[0])} to {fmt_dsname(*to_iter[-1])}'
 			def update_status(ix, d, sliceno, rehash):
 				update('%s, %d/%d (%s)' % (msg_head, ix, len(to_iter), fmt_dsname(d, sliceno, rehash)))
 		with status(msg_head) as update:
@@ -925,7 +925,7 @@ def new(columns, filenames, compressions, lines, minmax={}, filename=None, hashl
 		if hashlabel is not None:
 			hashlabel = uni(hashlabel)
 			if hashlabel not in columns:
-				raise DatasetUsageError("Hashlabel (%r) does not exist" % (hashlabel,))
+				raise DatasetUsageError(f"Hashlabel ({hashlabel!r}) does not exist")
 		res = Dataset(_new_dataset_marker, name)
 		res._data.lines = list(Dataset._linefixup(lines))
 		res._data.hashlabel = hashlabel
@@ -948,7 +948,7 @@ def append(self, columns, filenames, compressions, lines, minmax={}, filename=No
 		if hashlabel_override:
 			self._data.hashlabel = hashlabel
 		elif hashlabel is not None and self.hashlabel != hashlabel:
-			raise DatasetUsageError("Hashlabel mismatch %r != %r" % (self.hashlabel, hashlabel,))
+			raise DatasetUsageError(f"Hashlabel mismatch {self.hashlabel!r} != {hashlabel!r}")
 		if self._linefixup(lines) != self.lines:
 			from accelerator.g import job
 			raise DatasetUsageError("New columns don't have the same number of lines as parent columns (trying to append %s to %s, expected %r but got %r)" % (quote('%s/%s' % (job, name,)), self.quoted, self.lines, self._linefixup(lines),))
@@ -996,7 +996,7 @@ def _append(self, columns, filenames, compressions, minmax, filename, caption, p
 		if set(columns) != set(compressions):
 			raise DatasetUsageError("columns and compressions don't have the same keys")
 		if self.job and (self.job != job or self.name != name):
-			self._data.parent = '%s/%s' % (self.job, self.name,)
+			self._data.parent = f'{self.job}/{self.name}'
 		self.job = job
 		self.name = name
 		self.fs_name = _fs_name(name)
@@ -1011,11 +1011,11 @@ def _append(self, columns, filenames, compressions, minmax, filename, caption, p
 			filtered_columns = {k: v for k, v in self._data.columns.items() if k in column_filter}
 			left_over = column_filter - set(filtered_columns)
 			if left_over:
-				raise DatasetUsageError("Columns in filter not available in dataset: %r" % (left_over,))
+				raise DatasetUsageError(f"Columns in filter not available in dataset: {left_over!r}")
 			self._data.columns = filtered_columns
 		for n, (t, none_support) in sorted(columns.items()):
 			if t not in _type2iter:
-				raise DatasetUsageError('Unknown type %s on column %s' % (t, n,))
+				raise DatasetUsageError(f'Unknown type {t} on column {n}')
 			mm = minmax.get(n, (None, None,))
 			t = uni(t)
 			self._data.columns[n] = DatasetColumn(
@@ -1044,7 +1044,7 @@ def _update_caches(self):
 		except NoSuchDatasetError:
 			j, n = self._data['previous'].split('/', 1)
 			if self.job == j and n in _datasetwriters:
-				raise DatasetUsageError('previous dataset %r must be .finish()ed first.' % (n,))
+				raise DatasetUsageError(f'previous dataset {n!r} must be .finish()ed first.')
 			else:
 				raise
 		if d:
@@ -1097,7 +1097,7 @@ def getsize(sliceno):
 		location = c.location.split('/', 1) # the jobid might have % in it, so split it off
 		self._data.columns[n] = c._replace(
 			offsets=offsets,
-			location='%s/%s' % (location[0], location[1] % ('m',)),
+			location=f"{location[0]}/{location[1] % ('m',)}",
 		)
 
 	def _maybe_merge_fully(self, columns):
@@ -1116,14 +1116,14 @@ def _maybe_merge_fully(self, columns):
 			if z > 16 * 524288: # arbitrary guess of good size
 				return
 		m_fn = self._name('merged')
-		m_location = '%s/%s' % (self.job, m_fn,)
+		m_location = f'{self.job}/{m_fn}'
 		with open(m_fn, 'wb') as m_fh:
 			for n in columns:
 				dc = self._data.columns[n]
 				c_fn = self.column_filename(n)
 				with open(c_fn, 'rb') as c_fh:
 					data = c_fh.read()
-				assert len(data) > max(dc.offsets), '%s is too short' % (c_fn,)
+				assert len(data) > max(dc.offsets), f'{c_fn} is too short'
 				os.unlink(c_fn)
 				pos = m_fh.tell()
 				m_offsets = [False if o is False else o + pos for o in dc.offsets]
@@ -1141,7 +1141,7 @@ def _name(self, thing):
 			assert thing == 'pickle'
 			return self.name + '/dataset.pickle'
 		else:
-			return '%s.%s' % (self.fs_name, thing[0])
+			return f'{self.fs_name}.{thing[0]}'
 
 _datasetwriters = {}
 _datasets_written = []
@@ -1238,13 +1238,13 @@ def __new__(cls, columns={}, filename=None, hashlabel=None, hashlabel_override=F
 		from accelerator.g import running, job
 		if running == 'analysis':
 			if name not in _datasetwriters:
-				raise DatasetUsageError('Dataset with name "%s" not created' % (name,))
+				raise DatasetUsageError(f'Dataset with name "{name}" not created')
 			if columns or filename or hashlabel or hashlabel_override or caption or previous or parent or meta_only or for_single_slice is not None:
 				raise DatasetUsageError("Don't specify any arguments (except optionally name) in analysis")
 			return _datasetwriters[name]
 		else:
 			if name in _datasetwriters or os.path.exists(_fs_name(name) + '.p'):
-				raise DatasetUsageError('Duplicate dataset name "%s"' % (name,))
+				raise DatasetUsageError(f'Duplicate dataset name "{name}"')
 			fs_name = _fs_name(name) + '.d'
 			if not os.path.exists('DS'):
 				os.mkdir('DS')
@@ -1257,7 +1257,7 @@ def __new__(cls, columns={}, filename=None, hashlabel=None, hashlabel_override=F
 			obj.caption = uni(caption)
 			obj.previous = _dsid(previous)
 			obj.name = name
-			obj.ds_name = '%s/%s' % (job, name,)
+			obj.ds_name = f'{job}/{name}'
 			obj.quoted_ds_name = quote(obj.ds_name)
 			obj.fs_name = fs_name
 			obj.columns = {}
@@ -1274,13 +1274,13 @@ def __new__(cls, columns={}, filename=None, hashlabel=None, hashlabel_override=F
 				if not hashlabel_override:
 					if obj.hashlabel is not None:
 						if obj.hashlabel != obj.parent.hashlabel:
-							raise DatasetUsageError("Hashlabel mismatch %r != %r" % (obj.hashlabel, obj.parent.hashlabel,))
+							raise DatasetUsageError(f"Hashlabel mismatch {obj.hashlabel!r} != {obj.parent.hashlabel!r}")
 					elif obj.parent.hashlabel in columns:
 						obj.hashlabel = obj.parent.hashlabel
 				parent_cols = obj.parent.columns
 				unknown_discards = discard_columns - set(parent_cols)
 				if unknown_discards:
-					raise DatasetUsageError("Can't discard non-existant columns %r" % (unknown_discards,))
+					raise DatasetUsageError(f"Can't discard non-existant columns {unknown_discards!r}")
 				obj._column_filter = set(parent_cols) - discard_columns
 			else:
 				if discard_columns:
@@ -1319,7 +1319,7 @@ def add(self, colname, coltype, default=_nodefault, none_support=_nodefault):
 		colname = uni(colname)
 		coltype = uni(coltype)
 		if colname in self.columns:
-			raise DatasetUsageError("Column %s already exists" % (colname,))
+			raise DatasetUsageError(f"Column {colname} already exists")
 		try:
 			typed_writer(coltype) # gives error for unknown types
 		except ValueError as e:
@@ -1376,7 +1376,7 @@ def _mkwriters(self, sliceno, filtered=True):
 		if not self.columns:
 			raise DatasetUsageError("No columns in dataset")
 		if self.hashlabel is not None and self.hashlabel not in self.columns:
-			raise DatasetUsageError("Hashed column (%r) missing" % (self.hashlabel,))
+			raise DatasetUsageError(f"Hashed column ({self.hashlabel!r}) missing")
 		self._started = 2 - filtered
 		if self.meta_only:
 			return
@@ -1385,7 +1385,7 @@ def _mkwriters(self, sliceno, filtered=True):
 			if self._copy_mode:
 				coltype = _copy_mode_overrides.get(coltype, coltype)
 			wt = typed_writer(coltype)
-			error_extra = ' (column %s (type %s) in %s)' % (quote(colname), coltype, self.quoted_ds_name,)
+			error_extra = f' (column {quote(colname)} (type {coltype}) in {self.quoted_ds_name})'
 			kw = {'none_support': none_support, 'error_extra': error_extra, 'compression': 'gzip'}
 			if default is not _nodefault:
 				kw['default'] = default
@@ -1434,19 +1434,19 @@ def write_dict(values):
 		f = ['def write(' + ', '.join(names) + '):']
 		f_list = ['def write_list(values):']
 		if len(names) == 1: # only the hashlabel, no check needed
-			f.append(' %s(%s)' % (w_names[0], names[0],))
-			f_list.append(' %s(values[0])' % (w_names[0],))
+			f.append(f' {w_names[0]}({names[0]})')
+			f_list.append(f' {w_names[0]}(values[0])')
 		else:
 			if hl is not None:
-				f.append(' if %s(%s):' % (w_names[hix], names[hix],))
+				f.append(f' if {w_names[hix]}({names[hix]}):')
 				f_list.append(' if %s(values[%d]):' % (w_names[hix], hix,))
 			for ix in range(len(names)):
 				if ix != hix:
-					f.append('  %s(%s)' % (w_names[ix], names[ix],))
+					f.append(f'  {w_names[ix]}({names[ix]})')
 					f_list.append('  %s(values[%d])' % (w_names[ix], ix,))
 			if hl is not None and not discard:
-				f.append(' else: raise %s(%r)' % (errcls, wrong_slice_msg,))
-				f_list.append(' else: raise %s(%r)' % (errcls, wrong_slice_msg,))
+				f.append(f' else: raise {errcls}({wrong_slice_msg!r})')
+				f_list.append(f' else: raise {errcls}({wrong_slice_msg!r})')
 		eval(compile('\n'.join(f), '', 'exec'), w_d)
 		self.write = w_d['write']
 		eval(compile('\n'.join(f_list), '', 'exec'), w_d)
@@ -1516,7 +1516,7 @@ def hashwrap(v):
 				w_d[name_hsh] = hashwrap
 			else:
 				w_d[name_hsh] = hashfunc
-			prefix = '%s = %s[%s(' % (name_w_l, name_writers, name_hsh,)
+			prefix = f'{name_w_l} = {name_writers}[{name_hsh}('
 			hix = self._order.index(hl)
 			f_____.append('%s%s) %% %d]' % (prefix, names[hix], slices,))
 			f_list.append('%sv[%d]) %% %d]' % (prefix, hix, slices,))
@@ -1524,7 +1524,7 @@ def hashwrap(v):
 		else:
 			from itertools import cycle
 			w_d[name_cyc] = cycle(range(slices))
-			code = '%s = %s[%s(%s)]' % (name_w_l, name_writers, name_next, name_cyc,)
+			code = f'{name_w_l} = {name_writers}[{name_next}({name_cyc})]'
 			f_____.append(code)
 			f_list.append(code)
 			f_dict.append(code)
@@ -1604,18 +1604,18 @@ def finish(self):
 		if self._finished:
 			return self._finished
 		if not (self._started or self.meta_only or self._lens):
-			raise DatasetUsageError("DatasetWriter %r was never started (.get_split_write*() or .set_slice(), or .discard() it)" % (self.name,))
+			raise DatasetUsageError(f"DatasetWriter {self.name!r} was never started (.get_split_write*() or .set_slice(), or .discard() it)")
 		self.close()
 		if set(self._compressions) != set(self.columns):
 			missing = set(self.columns) - set(self._compressions)
 			extra = set(self._compressions) - set(self.columns)
-			raise DatasetUsageError("compressions don't match columns in %s, missing %s, extra %s" % (self.name, missing or "none", extra or "none",))
+			raise DatasetUsageError(f"compressions don't match columns in {self.name}, missing {missing or 'none'}, extra {extra or 'none'}")
 		if len(self._lens) != slices:
 			if self._allow_missing_slices:
 				for sliceno in range(slices):
 					self._lens[sliceno] = self._lens.get(sliceno, 0)
 			else:
-				raise DatasetUsageError("Not all slices written, missing %r" % (set(range(slices)) - set(self._lens),))
+				raise DatasetUsageError(f"Not all slices written, missing {set(range(slices)) - set(self._lens)!r}")
 		args = dict(
 			columns={k: (v[0].split(':')[-1], v[2]) for k, v in self.columns.items()},
 			filenames=self._filenames,
@@ -1723,7 +1723,7 @@ def range(self, colname, start=None, stop=None):
 		"""Filter out only datasets where colname has values in range(start, stop)"""
 		def predicate(ds):
 			if colname not in ds.columns:
-				raise DatasetUsageError('Dataset %s does not have column %r' % (ds.quoted, colname,))
+				raise DatasetUsageError(f'Dataset {ds.quoted} does not have column {colname!r}')
 			col = ds.columns[colname]
 			if col.min is not None:
 				return (stop is None or col.min < stop) and (start is None or col.max >= start)
diff --git a/accelerator/deptree.py b/accelerator/deptree.py
index 1dc7d8f8..87070a6e 100644
--- a/accelerator/deptree.py
+++ b/accelerator/deptree.py
@@ -74,10 +74,10 @@ def _fix_jobids(self, key):
 		for jobid_name in method_wants:
 			if isinstance(jobid_name, str_types):
 				value = data.get(jobid_name)
-				assert value is None or isinstance(value, str), 'Input %s on %s not a string as required' % (jobid_name, method,)
+				assert value is None or isinstance(value, str), f'Input {jobid_name} on {method} not a string as required'
 			elif isinstance(jobid_name, list):
 				if len(jobid_name) != 1 or not isinstance(jobid_name[0], str_types):
-					raise OptionException('Bad %s item on %s: %s' % (key, method, repr(jobid_name),))
+					raise OptionException(f'Bad {key} item on {method}: {jobid_name!r}')
 				jobid_name = jobid_name[0]
 				value = data.get(jobid_name)
 				if value:
@@ -85,14 +85,14 @@ def _fix_jobids(self, key):
 						value = [e.strip() for e in value.split(',')]
 				else:
 					value = []
-				assert isinstance(value, list), 'Input %s on %s not a list or string as required' % (jobid_name, method,)
+				assert isinstance(value, list), f'Input {jobid_name} on {method} not a list or string as required'
 			else:
-				raise OptionException('%s item of unknown type %s on %s: %s' % (key, type(jobid_name), method, repr(jobid_name),))
+				raise OptionException(f'{key} item of unknown type {type(jobid_name)} on {method}: {jobid_name!r}')
 			res[jobid_name] = value
 		self.params[key] = res
 		spill = set(data) - set(res)
 		if spill:
-			raise OptionException('Unknown %s on %s: %s' % (key, method, ', '.join(sorted(spill)),))
+			raise OptionException(f"Unknown {key} on {method}: {', '.join(sorted(spill))}")
 
 	def _fix_options(self, fill_in):
 		method = self.method
@@ -107,13 +107,13 @@ def typefuzz(t):
 		def convert(default_v, v):
 			if isinstance(default_v, RequiredOption):
 				if v is None and not default_v.none_ok:
-					raise OptionException('Option %s on method %s requires a non-None value (%r)' % (k, method, default_v.value,))
+					raise OptionException(f'Option {k} on method {method} requires a non-None value ({default_v.value!r})')
 				default_v = default_v.value
 			if default_v is None or v is None:
 				if isinstance(default_v, _OptionString):
-					raise OptionException('Option %s on method %s requires a non-empty string value' % (k, method,))
+					raise OptionException(f'Option {k} on method {method} requires a non-empty string value')
 				if hasattr(default_v, '_valid') and v not in default_v._valid:
-					raise OptionException('Option %s on method %s requires a value in %s' % (k, method, default_v._valid,))
+					raise OptionException(f'Option {k} on method {method} requires a value in {default_v._valid}')
 				if isinstance(default_v, OptionDefault):
 					v = default_v.default
 				return v
@@ -145,13 +145,13 @@ def convert(default_v, v):
 							ok = True
 							break
 					if not ok:
-						raise OptionException('%r not a permitted value for option %s on method %s (%s)' % (v, k, method, default_v._valid))
+						raise OptionException(f'{v!r} not a permitted value for option {k} on method {method} ({default_v._valid})')
 				return v or None
 			if isinstance(default_v, str_types + num_types) and isinstance(v, str_types + num_types):
 				if isinstance(default_v, _OptionString):
 					v = str(v)
 					if not v:
-						raise OptionException('Option %s on method %s requires a non-empty string value' % (k, method,))
+						raise OptionException(f'Option {k} on method {method} requires a non-empty string value')
 					return v
 				if isinstance(default_v, str) and isinstance(v, bytes):
 					return v.decode('utf-8')
@@ -174,7 +174,7 @@ def convert(default_v, v):
 				try:
 					return typing_conv[default_v.__name__](v)
 				except Exception:
-					raise OptionException('Failed to convert option %s %r to %s on method %s' % (k, v, default_v, method,))
+					raise OptionException(f'Failed to convert option {k} {v!r} to {default_v} on method {method}')
 			if isinstance(v, str_types) and not v:
 				return type(default_v)()
 			if isinstance(default_v, JobWithFile) or default_v is JobWithFile:
@@ -182,13 +182,13 @@ def convert(default_v, v):
 				if default_v is JobWithFile:
 					default_v = defaults
 				if not isinstance(v, (list, tuple,)) or not (2 <= len(v) <= 4):
-					raise OptionException('Option %s (%r) on method %s is not %s compatible' % (k, v, method, type(default_v)))
+					raise OptionException(f'Option {k} ({v!r}) on method {method} is not {type(default_v)} compatible')
 				v = tuple(v) + defaults[len(v):] # so all of default_v gets convert()ed.
 				v = [convert(dv, vv) for dv, vv in zip(default_v, v)]
 				return JobWithFile(*v)
 			if type(default_v) != type:
 				default_v = type(default_v)
-			raise OptionException('Failed to convert option %s of %s to %s on method %s' % (k, type(v), default_v, method,))
+			raise OptionException(f'Failed to convert option {k} of {type(v)} to {default_v} on method {method}')
 		for k, v in iteritems(self.params['options']):
 			if k in options:
 				try:
@@ -197,9 +197,9 @@ def convert(default_v, v):
 					raise
 				except Exception:
 					print_exc(file=sys.stderr)
-					raise OptionException('Failed to convert option %s on method %s' % (k, method,))
+					raise OptionException(f'Failed to convert option {k} on method {method}')
 			else:
-				raise OptionException('Unknown option %s on method %s' % (k, method,))
+				raise OptionException(f'Unknown option {k} on method {method}')
 		if fill_in:
 			missing = set(options) - set(res_options)
 			missing_required = missing & self.methods.params[method].required
diff --git a/accelerator/dispatch.py b/accelerator/dispatch.py
index 988a8a77..7a07c818 100644
--- a/accelerator/dispatch.py
+++ b/accelerator/dispatch.py
@@ -81,7 +81,7 @@ def launch(workdir, setup, config, Methods, active_workdirs, slices, concurrency
 		print_prefix = ''
 	else:
 		print_prefix = '    '
-	print('%s| %s [%s] |' % (print_prefix, jobid, method,))
+	print(f'{print_prefix}| {jobid} [{method}] |')
 	args = dict(
 		workdir=workdir,
 		slices=slices,
@@ -109,7 +109,7 @@ def launch(workdir, setup, config, Methods, active_workdirs, slices, concurrency
 				pass
 			# The dying process won't have sent an end message, so it has
 			# the endwait time until we SIGKILL it.
-			print('%s| %s [%s]  failed!    (%5.1fs) |' % (print_prefix, jobid, method, monotonic() - starttime))
+			print(f'{print_prefix}| {jobid} [{method}]  failed!    ({monotonic() - starttime:5.1f}s) |')
 		# There is a race where stuff on the status socket has not arrived when
 		# the sending process exits. This is basically benign, but let's give
 		# it a chance to arrive to cut down on confusing warnings.
@@ -130,5 +130,5 @@ def launch(workdir, setup, config, Methods, active_workdirs, slices, concurrency
 			pass
 	if status:
 		raise JobError(jobid, method, status)
-	print('%s| %s [%s]  completed. (%5.1fs) |' % (print_prefix, jobid, method, monotonic() - starttime))
+	print(f'{print_prefix}| {jobid} [{method}]  completed. ({monotonic() - starttime:5.1f}s) |')
 	return data
diff --git a/accelerator/dsutil.py b/accelerator/dsutil.py
index 376dbe34..2d47316b 100644
--- a/accelerator/dsutil.py
+++ b/accelerator/dsutil.py
@@ -65,12 +65,12 @@
 
 def typed_writer(typename):
 	if typename not in _convfuncs:
-		raise ValueError("Unknown writer for type %s" % (typename,))
+		raise ValueError(f"Unknown writer for type {typename}")
 	return _convfuncs[typename]
 
 def typed_reader(typename):
 	if typename not in _type2iter:
-		raise ValueError("Unknown reader for type %s" % (typename,))
+		raise ValueError(f"Unknown reader for type {typename}")
 	return _type2iter[typename]
 
 _nodefault = object()
diff --git a/accelerator/error.py b/accelerator/error.py
index 6f738cf9..086d1bdf 100644
--- a/accelerator/error.py
+++ b/accelerator/error.py
@@ -69,15 +69,15 @@ class BuildError(AcceleratorError):
 
 class JobError(BuildError):
 	def __init__(self, job, method, status):
-		AcceleratorError.__init__(self, "Failed to build %s (%s)" % (job, method,))
+		AcceleratorError.__init__(self, f"Failed to build {job} ({method})")
 		self.job = job
 		self.method = method
 		self.status = status
 
 	def format_msg(self):
-		res = ["%s (%s):" % (self.job, self.method,)]
+		res = [f"{self.job} ({self.method}):"]
 		for component, msg in self.status.items():
-			res.append("  %s:" % (component,))
+			res.append(f"  {component}:")
 			res.append("    %s" % (msg.replace("\n", "\n    "),))
 		return "\n".join(res)
 
diff --git a/accelerator/examples/a_example_returninprepanasyn.py b/accelerator/examples/a_example_returninprepanasyn.py
index be1dff66..d5d75d80 100644
--- a/accelerator/examples/a_example_returninprepanasyn.py
+++ b/accelerator/examples/a_example_returninprepanasyn.py
@@ -6,7 +6,7 @@ def prepare():
 
 
 def analysis(sliceno, prepare_res):
-	return 'this is analysis %s with prepare_res=%s' % (str(sliceno), prepare_res)
+	return f'this is analysis {sliceno!s} with prepare_res={prepare_res}'
 
 
 def synthesis(analysis_res, prepare_res):
diff --git a/accelerator/examples/a_example_writeslicedfile.py b/accelerator/examples/a_example_writeslicedfile.py
index 23a20b1f..46b16fe6 100644
--- a/accelerator/examples/a_example_writeslicedfile.py
+++ b/accelerator/examples/a_example_writeslicedfile.py
@@ -11,9 +11,9 @@ def analysis(sliceno, job):
 def synthesis(job):
 	# ...and one file in the synthesis process...
 	filename = 'myfile2'
-	data = 'this is job %s synthesis' % (job,)
+	data = f'this is job {job} synthesis'
 	job.save(data, filename)
 
 	# ...and let's return some data too.
-	returndata = 'this is job %s return value' % (job,)
+	returndata = f'this is job {job} return value'
 	return returndata
diff --git a/accelerator/examples/build_dsexample-chain.py b/accelerator/examples/build_dsexample-chain.py
index c965d098..645b21f9 100644
--- a/accelerator/examples/build_dsexample-chain.py
+++ b/accelerator/examples/build_dsexample-chain.py
@@ -26,9 +26,9 @@ def main(urd):
 
 	prt()
 	prt('To go back in chain and investigate datasets, try')
-	prt.command('ax ds %s' % (imp,))
-	prt.command('ax ds %s~' % (imp,))
-	prt.command('ax ds %s~~' % (imp,))
+	prt.command(f'ax ds {imp}')
+	prt.command(f'ax ds {imp}~')
+	prt.command(f'ax ds {imp}~~')
 	prt('Note that ~~ can also be written ~2 etc.')
 
 	prt()
diff --git a/accelerator/examples/build_dsexample-create.py b/accelerator/examples/build_dsexample-create.py
index dcd58e7b..1a8d6664 100644
--- a/accelerator/examples/build_dsexample-create.py
+++ b/accelerator/examples/build_dsexample-create.py
@@ -19,4 +19,4 @@ def main(urd):
 
 	prt()
 	prt('For convenience, the jobid can be used as a reference to the default')
-	prt('dataset in a job.  The full name is "%s/default".' % (job,))
+	prt(f'dataset in a job.  The full name is "{job}/default".')
diff --git a/accelerator/examples/build_dsexample-many_ds.py b/accelerator/examples/build_dsexample-many_ds.py
index 861c9196..487335e8 100644
--- a/accelerator/examples/build_dsexample-many_ds.py
+++ b/accelerator/examples/build_dsexample-many_ds.py
@@ -20,4 +20,4 @@ def main(urd):
 
 	prt()
 	prt('Print contents of a specific dataset like this')
-	prt.command('ax cat -H %s/third' % (job,))
+	prt.command(f'ax cat -H {job}/third')
diff --git a/accelerator/examples/build_example-depend_extra.py b/accelerator/examples/build_example-depend_extra.py
index 98bcb46d..97642623 100644
--- a/accelerator/examples/build_example-depend_extra.py
+++ b/accelerator/examples/build_example-depend_extra.py
@@ -16,4 +16,4 @@ def main(urd):
 
 	prt()
 	prt('source code is here:')
-	prt.plain(join(dirname(__file__), 'a_%s.py' % (job.method,)))
+	prt.plain(join(dirname(__file__), f'a_{job.method}.py'))
diff --git a/accelerator/examples/build_example-equiv_hashes.py b/accelerator/examples/build_example-equiv_hashes.py
index 744d8be1..7047fdee 100644
--- a/accelerator/examples/build_example-equiv_hashes.py
+++ b/accelerator/examples/build_example-equiv_hashes.py
@@ -15,7 +15,7 @@ def main(urd):
 	thehash = job.params.hash
 	prt()
 	prt('Take the hash from the built job:')
-	prt.output('"%s"' % (thehash,))
+	prt.output(f'"{thehash}"')
 	prt('and add it to the method like this')
 	prt.output('"equivalent_hashes = {\'whatever\': (\'%s\',)}"' % (thehash,))
 
@@ -32,4 +32,4 @@ def main(urd):
 	prt('to the old one.')
 	prt()
 	prt('Method source file is here')
-	prt.plain(join(dirname(__file__), 'a_%s.py' % (job.method,)))
+	prt.plain(join(dirname(__file__), f'a_{job.method}.py'))
diff --git a/accelerator/examples/build_example-files.py b/accelerator/examples/build_example-files.py
index 35b510aa..fa3776f4 100644
--- a/accelerator/examples/build_example-files.py
+++ b/accelerator/examples/build_example-files.py
@@ -10,7 +10,7 @@ def main(urd):
 	job1 = urd.build('example_writeslicedfile')
 
 	prt()
-	prt('These are the files created by / located in job %s.' % (job1,))
+	prt(f'These are the files created by / located in job {job1}.')
 	prt.output(job1.files())
 
 	prt()
@@ -23,13 +23,13 @@ def main(urd):
 	)
 
 	prt()
-	prt('Read and print stored stdout from %s synthesis' % (job2,))
+	prt(f'Read and print stored stdout from {job2} synthesis')
 	prt.output(job2.output('synthesis'))
 	prt()
-	prt('Read and print stored stdout from %s everything' % (job2,))
+	prt(f'Read and print stored stdout from {job2} everything')
 	prt.output(job2.output())
 	prt()
-	prt('Read and print stored stdout from %s analysis process 2' % (job2,))
+	prt(f'Read and print stored stdout from {job2} analysis process 2')
 	prt.output(job2.output(2))
 
 	prt()
@@ -40,4 +40,4 @@ def main(urd):
 		prt.output(pickle.load(fh))
 
 	prt('To see all files stored in a job, try')
-	prt.command('ax job %s' % (job1,))
+	prt.command(f'ax job {job1}')
diff --git a/accelerator/examples/build_example-options.py b/accelerator/examples/build_example-options.py
index cdd4b5b7..4419b470 100644
--- a/accelerator/examples/build_example-options.py
+++ b/accelerator/examples/build_example-options.py
@@ -22,11 +22,11 @@ def main(urd):
 	prt('The job will print its options to stdout.')
 	prt()
 	prt('See the options as the job sees them by running')
-	prt.command('ax job -O %s' % (job,))
+	prt.command(f'ax job -O {job}')
 	prt('The "ax job" command will also show the job\'s options')
-	prt.command('ax job %s' % (job,))
+	prt.command(f'ax job {job}')
 	prt('See everything using')
-	prt.command('ax job -o %s' % (job,))
+	prt.command(f'ax job -o {job}')
 
 	prt()
 	prt.header('Short and long version (see code)')
diff --git a/accelerator/examples/build_tutorial01.py b/accelerator/examples/build_tutorial01.py
index 5d8e0390..8354f28a 100644
--- a/accelerator/examples/build_tutorial01.py
+++ b/accelerator/examples/build_tutorial01.py
@@ -38,9 +38,9 @@ def main(urd):
 			reference to the job that created the dataset as a reference
 			to the default dataset inside the job.  I.e.
 		''')
-		prt.command('ax ds %s' % (imp,))
+		prt.command(f'ax ds {imp}')
 		prt('is equivalent to')
-		prt.command('ax ds %s/default' % (imp,))
+		prt.command(f'ax ds {imp}/default')
 		prt('which is the formally correct way to refer to the dataset.')
 
 	prt()
diff --git a/accelerator/examples/build_tutorial02.py b/accelerator/examples/build_tutorial02.py
index e5b88f2f..b8c550a2 100644
--- a/accelerator/examples/build_tutorial02.py
+++ b/accelerator/examples/build_tutorial02.py
@@ -37,8 +37,8 @@ def main(urd):
 	prt()
 	with prt.header('VISUALISING A JOB\'S DEPENDENCIES'):
 		prt('View the job\'s metadata using')
-		prt.command('ax job %s' % (imp,))
-		prt('We can see that the dataset "%s" is input to this job.' % (imp.params.datasets.source,))
+		prt.command(f'ax job {imp}')
+		prt(f'We can see that the dataset "{imp.params.datasets.source}" is input to this job.')
 
 	prt()
 	with prt.header('REFERENCES TO ALL JOBS ARE STORED IN THE "urd.joblist" OBJECT:'):
@@ -54,7 +54,7 @@ def main(urd):
 
 			Take a look at the dataset created by dataset_hashpart:
 		''')
-		prt.command('ax ds %s' % (imp,))
+		prt.command(f'ax ds {imp}')
 		prt('''
 			The asterisk on the row corresponding to the "String" column
 			indicates that the dataset is hash partitioned based the values
@@ -63,4 +63,4 @@ def main(urd):
 
 			We can also see how many rows there are in each slice by typing
 		''')
-		prt.command('ax ds -s %s' % (imp,))
+		prt.command(f'ax ds -s {imp}')
diff --git a/accelerator/examples/build_tutorial03.py b/accelerator/examples/build_tutorial03.py
index ee4daef6..10886569 100644
--- a/accelerator/examples/build_tutorial03.py
+++ b/accelerator/examples/build_tutorial03.py
@@ -64,16 +64,16 @@ def main(urd):
 	with prt.header('INSPECTING DATASET CHAINS'):
 		prt('  The flags -s, -S, and -c to "ax ds" are useful when looking')
 		prt('  at chained datasets')
-		prt.command('ax ds -s %s' % (imp,))
-		prt.command('ax ds -S %s' % (imp,))
-		prt.command('ax ds -c %s' % (imp,))
+		prt.command(f'ax ds -s {imp}')
+		prt.command(f'ax ds -S {imp}')
+		prt.command(f'ax ds -c {imp}')
 		prt('As always, see info and more options using')
 		prt.command('ax ds --help')
 
 	prt()
 	with prt.header('PRINTING A DATASET CHAIN'):
 		prt('This is a small example, so we can print all data using')
-		prt.command('ax cat -c %s' % (imp,))
+		prt.command(f'ax cat -c {imp}')
 
 	prt()
 	with prt.header('GREPPING'):
@@ -82,4 +82,4 @@ def main(urd):
 			"String" column, but show "Date", "Float", and "Int"
 			columns only.
 		''')
-		prt.command('ax grep bb -c -g String %s Date Float Int' % (imp,))
+		prt.command(f'ax grep bb -c -g String {imp} Date Float Int')
diff --git a/accelerator/examples/build_tutorial04.py b/accelerator/examples/build_tutorial04.py
index e856514f..82f88266 100644
--- a/accelerator/examples/build_tutorial04.py
+++ b/accelerator/examples/build_tutorial04.py
@@ -71,4 +71,4 @@ def main(urd):
 		prt()
 		prt('Try')
 		prt.command('ax job -O', job)
-		prt('to print this output from the %s job to the terminal.' % (job.method,))
+		prt(f'to print this output from the {job.method} job to the terminal.')
diff --git a/accelerator/examples/build_tutorial05.py b/accelerator/examples/build_tutorial05.py
index 6bac03c3..ab0511aa 100644
--- a/accelerator/examples/build_tutorial05.py
+++ b/accelerator/examples/build_tutorial05.py
@@ -53,11 +53,11 @@ def main(urd):
 		urd.finish(key)
 
 	prt()
-	prt('''
-		Now, references to everything that has been built, including
-		job dependencies, is stored in the Urd server using the.
-		key "/%s".
-	''' % (key,))
+	prt(f'''
+\t\tNow, references to everything that has been built, including
+\t\tjob dependencies, is stored in the Urd server using the.
+\t\tkey "/{key}".
+\t''')
 
 	prt()
 	with prt.header('View all Urd lists.'):
@@ -70,10 +70,10 @@ def main(urd):
 	prt()
 	with prt.header('Inspecting all sessions in a list.'):
 		prt('All sessions are timestamped.  To see all timestamps')
-		prt('and captions in "%s" since timestamp zero, do' % (key,))
-		prt.command('ax urd %s/since/0' % (key,))
+		prt(f'and captions in "{key}" since timestamp zero, do')
+		prt.command(f'ax urd {key}/since/0')
 		prt('or equivalently')
-		prt.command('ax urd %s/' % (key,))
+		prt.command(f'ax urd {key}/')
 		prt('the output from this command looks something like this (try it)')
 		for ts in urd.since(key, 0):
 			prt.output(ts, urd.peek(key, ts).caption)
@@ -81,8 +81,8 @@ def main(urd):
 	prt()
 	with prt.header('Inspecting individual Urd items.'):
 		prt('We can look at an individual Urd-item like this')
-		prt.command('ax urd %s/3' % (key,))
-		prt('which corresponds to the list in key "%s" at timestamp 3.' % (key,))
+		prt.command(f'ax urd {key}/3')
+		prt(f'which corresponds to the list in key "{key}" at timestamp 3.')
 		prt('(Timestamps can be dates, datetimes, integers, or tuples')
 		prt('of date/datetimes and integers.)')
 
diff --git a/accelerator/examples/build_urdexample-basic.py b/accelerator/examples/build_urdexample-basic.py
index 80846411..92fbda3a 100644
--- a/accelerator/examples/build_urdexample-basic.py
+++ b/accelerator/examples/build_urdexample-basic.py
@@ -14,7 +14,7 @@ def main(urd):
 
 	prt()
 	prt('Create and Urd item containing a joblist of one job.')
-	prt('The name of the Urd list is "%s".' % (listname,))
+	prt(f'The name of the Urd list is "{listname}".')
 	urd.begin(listname, timestamp, caption='you may assign a caption here')
 	urd.build('example_returnhelloworld')
 	urd.finish(listname)
@@ -30,34 +30,34 @@ def main(urd):
 	prt('# will do the same thing on the command line.')
 
 	prt()
-	prt('Here\'s a list of all entries in the list "%s"' % (listname,))
+	prt(f'Here\'s a list of all entries in the list "{listname}"')
 	for ts in urd.since(listname, 0):
 		prt.output(ts)
 
 	prt()
 	prt('The command')
-	prt.command('ax urd %s/since/0' % (listname,))
+	prt.command(f'ax urd {listname}/since/0')
 	prt('or')
-	prt.command('ax urd %s/' % (listname,))
+	prt.command(f'ax urd {listname}/')
 	prt('will do the same thing on the command line.')
 
 	prt()
 	prt('To see a specific entry, try')
-	prt.command('ax urd %s/%s' % (listname, timestamp))
+	prt.command(f'ax urd {listname}/{timestamp}')
 
 	prt()
 	prt('To see information about the a specific job in that Urd session')
-	prt.command('ax job :%s/%s:example1' % (listname, timestamp))
+	prt.command(f'ax job :{listname}/{timestamp}:example1')
 
 	prt()
 	prt('To see information about the last job in that Urd session')
-	prt.command('ax job :%s/%s:-1' % (listname, timestamp))
-	prt.command('ax job :%s/%s:' % (listname, timestamp))
+	prt.command(f'ax job :{listname}/{timestamp}:-1')
+	prt.command(f'ax job :{listname}/{timestamp}:')
 	prt('Note that the commands defaults to the _last_ item')
 
 	prt()
 	prt('To see information about the last job in the last Urd session')
-	prt.command('ax job :%s:' % (listname,))
+	prt.command(f'ax job :{listname}:')
 	prt('Note that the commands defaults to the _last_ item')
 
 	prt()
diff --git a/accelerator/examples/build_urdexample-many_items.py b/accelerator/examples/build_urdexample-many_items.py
index 67aed736..f75f2c48 100644
--- a/accelerator/examples/build_urdexample-many_items.py
+++ b/accelerator/examples/build_urdexample-many_items.py
@@ -14,7 +14,7 @@ def main(urd):
 	urd.truncate(listname, 0)
 
 	prt('Start by creating ten chained jobs.  Each job is associated')
-	prt('with a unique Urd-item in the "%s" Urd list.' % (listname,))
+	prt(f'with a unique Urd-item in the "{listname}" Urd list.')
 	starttime = date(2021, 8, 1)
 	for days in range(10):
 		timestamp = starttime + timedelta(days=days)
@@ -24,11 +24,11 @@ def main(urd):
 		urd.finish(listname)
 
 	prt()
-	prt('Here\'s a list of all entries in the list "%s"' % (listname,))
+	prt(f'Here\'s a list of all entries in the list "{listname}"')
 	for ts in urd.since(listname, 0):
-		prt.output(ts, '"%s"' % (urd.peek(listname, ts).caption,))
+		prt.output(ts, f'"{urd.peek(listname, ts).caption}"')
 	prt('This is available in the shell using')
-	prt.command('ax urd %s/' % (listname,))
+	prt.command(f'ax urd {listname}/')
 
 	prt()
 	prt('Here\'s the session for timestamp 2021-08-06')
@@ -39,4 +39,4 @@ def main(urd):
 
 	prt()
 	prt('To print this in a more human friendly format on the command line, try')
-	prt.command('    ax urd %s/2021-08-06' % (listname,))
+	prt.command(f'    ax urd {listname}/2021-08-06')
diff --git a/accelerator/extras.py b/accelerator/extras.py
index 41786b0c..2a51e3cc 100644
--- a/accelerator/extras.py
+++ b/accelerator/extras.py
@@ -40,8 +40,8 @@ def _fn(filename, jobid, sliceno):
 	if isinstance(filename, pathlib.Path):
 		filename = str(filename)
 	if filename.startswith('/'):
-		assert not jobid, "Don't specify full path (%r) and jobid (%s)." % (filename, jobid,)
-		assert not sliceno, "Don't specify full path (%r) and sliceno." % (filename,)
+		assert not jobid, f"Don't specify full path ({filename!r}) and jobid ({jobid})."
+		assert not sliceno, f"Don't specify full path ({filename!r}) and sliceno."
 	elif jobid:
 		filename = Job(jobid).filename(filename, sliceno)
 	elif sliceno is not None:
@@ -293,7 +293,7 @@ def debug_print_options(options, title=''):
 		print('-' * 53)
 	max_k = max(len(str(k)) for k in options)
 	for key, val in sorted(options.items()):
-		print("%s = %r" % (str(key).ljust(max_k), val))
+		print(f"{str(key).ljust(max_k)} = {val!r}")
 	print('-' * 53)
 
 
@@ -523,7 +523,7 @@ def __radd__(self, other):
 		return self.__class__(list.__add__(other, self))
 
 	def __repr__(self):
-		return '%s(%s)' % (self.__class__.__name__, list.__repr__(self))
+		return f'{self.__class__.__name__}({list.__repr__(self)})'
 
 class OptionEnumValue(str):
 
@@ -619,7 +619,7 @@ def __call__(self, example):
 		return _OptionString(example)
 	def __repr__(self):
 		if self:
-			return 'OptionString(%r)' % (str(self),)
+			return f'OptionString({str(self)!r})'
 		else:
 			return 'OptionString'
 OptionString = _OptionString('')
diff --git a/accelerator/graph.py b/accelerator/graph.py
index 42ca3984..aabc5ec9 100644
--- a/accelerator/graph.py
+++ b/accelerator/graph.py
@@ -249,7 +249,7 @@ def create_graph(inputitem, urdinfo=()):
 		else:
 			# dataset
 			n.columns = sorted((colname, dscol.type) for colname, dscol in n.payload.columns.items())
-			n.lines = "%d x % s" % (len(n.payload.columns), '{:,}'.format(sum(n.payload.lines)).replace(',', '_'))
+			n.lines = "%d x % s" % (len(n.payload.columns), f'{sum(n.payload.lines):,}'.replace(',', '_'))
 			n.ds = n.payload
 	graph.populate_with_neighbours()
 	return graph
@@ -314,7 +314,7 @@ def graph(inp, gtype):
 		jobid2urddep = defaultdict(list)
 		for key, urditem in inp.deps.items():
 			for _, jid in urditem.joblist:
-				jobid2urddep[jid].append("%s/%s" % (key, urditem.timestamp))
+				jobid2urddep[jid].append(f"{key}/{urditem.timestamp}")
 		jobid2urddep = {key: sorted(val) for key, val in jobid2urddep.items()}
 		jlist = inp.joblist
 		inp = tuple(Job(jid) for _, jid in jlist)
diff --git a/accelerator/iowrapper.py b/accelerator/iowrapper.py
index 96c1de73..bb428576 100644
--- a/accelerator/iowrapper.py
+++ b/accelerator/iowrapper.py
@@ -126,7 +126,7 @@ def reader(fd2pid, names, masters, slaves, process_name, basedir, is_main, is_bu
 		outputs = dict.fromkeys(masters, b'')
 		if len(fd2pid) == 2:
 			status_blacklist = set(fd2pid.values())
-			assert len(status_blacklist) == 1, "fd2pid should only map to 1 value initially: %r" % (fd2pid,)
+			assert len(status_blacklist) == 1, f"fd2pid should only map to 1 value initially: {fd2pid!r}"
 		else:
 			status_blacklist = ()
 			assert len(fd2pid) == 1, "fd2pid should have 1 or 2 elements initially"
diff --git a/accelerator/job.py b/accelerator/job.py
index d79237f4..83beaf6d 100644
--- a/accelerator/job.py
+++ b/accelerator/job.py
@@ -44,9 +44,9 @@ def dirnamematcher(name):
 def _assert_is_normrelpath(path, dirtype):
 	norm = os.path.normpath(path)
 	if (norm != path and norm + '/' != path) or norm.startswith('/'):
-		raise AcceleratorError('%r is not a normalised relative path' % (path,))
+		raise AcceleratorError(f'{path!r} is not a normalised relative path')
 	if norm == '..' or norm.startswith('../'):
-		raise AcceleratorError('%r is above the %s dir' % (path, dirtype))
+		raise AcceleratorError(f'{path!r} is above the {dirtype} dir')
 
 
 def _cachedprop(meth):
@@ -96,7 +96,7 @@ def __new__(cls, jobid, method=None):
 			obj.workdir, tmp = jobid.rsplit('-', 1)
 			obj.number = int(tmp)
 		except ValueError:
-			raise NoSuchJobError('Not a valid jobid: "%s".' % (jobid,))
+			raise NoSuchJobError(f'Not a valid jobid: "{jobid}".')
 		obj._cache = {}
 		if method:
 			obj._cache['method'] = method
@@ -134,7 +134,7 @@ def build_job(self):
 	@property
 	def path(self):
 		if self.workdir not in WORKDIRS:
-			raise NoSuchWorkdirError('Not a valid workdir: "%s"' % (self.workdir,))
+			raise NoSuchWorkdirError(f'Not a valid workdir: "{self.workdir}"')
 		return os.path.join(WORKDIRS[self.workdir], self)
 
 	def filename(self, filename, sliceno=None):
@@ -223,7 +223,7 @@ def output(self, what=None):
 		if isinstance(what, int):
 			fns = [what]
 		else:
-			assert what in (None, 'prepare', 'analysis', 'synthesis'), 'Unknown output %r' % (what,)
+			assert what in (None, 'prepare', 'analysis', 'synthesis'), f'Unknown output {what!r}'
 			if what in (None, 'analysis'):
 				fns = list(range(self.params.slices))
 				if what is None:
@@ -262,14 +262,14 @@ def link_result(self, filename='result.pickle', linkname=None, header=None, desc
 			else:
 				linkname += os.path.basename(filename)
 		source_fn = os.path.join(self.path, filename)
-		assert os.path.exists(source_fn), "Filename \"%s\" does not exist in jobdir \"%s\"!" % (filename, self.path)
+		assert os.path.exists(source_fn), f"Filename \"{filename}\" does not exist in jobdir \"{self.path}\"!"
 		result_directory = cfg['result_directory']
 		dest_fn = result_directory
 		for part in linkname.split('/'):
 			if not os.path.exists(dest_fn):
 				os.mkdir(dest_fn)
 			elif dest_fn != result_directory and os.path.islink(dest_fn):
-				raise AcceleratorError("Refusing to create link %r: %r is a symlink" % (linkname, dest_fn))
+				raise AcceleratorError(f"Refusing to create link {linkname!r}: {dest_fn!r} is a symlink")
 			dest_fn = os.path.join(dest_fn, part)
 		try:
 			os.remove(dest_fn + '_')
diff --git a/accelerator/launch.py b/accelerator/launch.py
index de29a6e1..afb7aa0d 100644
--- a/accelerator/launch.py
+++ b/accelerator/launch.py
@@ -323,7 +323,7 @@ def execute_process(workdir, jobid, slices, concurrency, index=None, workdirs=No
 
 	g.server_url       = server_url
 	g.running          = 'launch'
-	statmsg._start('%s %s' % (jobid, params.method,), parent_pid)
+	statmsg._start(f'{jobid} {params.method}', parent_pid)
 
 	def dummy():
 		pass
diff --git a/accelerator/metadata.py b/accelerator/metadata.py
index 58b13a7a..6da28b1f 100644
--- a/accelerator/metadata.py
+++ b/accelerator/metadata.py
@@ -459,7 +459,7 @@ def insert_metadata(filename, fh, job, size):
 					traceback.print_exc(file=sys.stderr)
 				if res:
 					break
-				print("Failed to generate %s metadata." % (name,), file=sys.stderr)
+				print(f"Failed to generate {name} metadata.", file=sys.stderr)
 	return res or [(0, size)]
 
 def extract_metadata(filename, fh):
diff --git a/accelerator/methods.py b/accelerator/methods.py
index 96c18424..be49306c 100644
--- a/accelerator/methods.py
+++ b/accelerator/methods.py
@@ -83,9 +83,9 @@ def __init__(self, server_config):
 			v = runner.get_ax_version()
 			if v != ax_version:
 				if runner.python == sys.executable:
-					raise AcceleratorError("Server is using accelerator %s but %s is currently installed, please restart server." % (ax_version, v,))
+					raise AcceleratorError(f"Server is using accelerator {ax_version} but {v} is currently installed, please restart server.")
 				else:
-					print("WARNING: Server is using accelerator %s but runner %r is using accelerator %s." % (ax_version, version, v,))
+					print(f"WARNING: Server is using accelerator {ax_version} but runner {version!r} is using accelerator {v}.")
 			w, f, h, p, d = runner.load_methods(package_list, data)
 			warnings.extend(w)
 			failed.extend(f)
@@ -123,9 +123,9 @@ def _check_package(self, package):
 			if not hasattr(package_mod, "__file__"):
 				raise ImportError("no __file__")
 		except ImportError:
-			raise AcceleratorError("Failed to import %s, maybe missing __init__.py?" % (package,))
+			raise AcceleratorError(f"Failed to import {package}, maybe missing __init__.py?")
 		if not package_mod.__file__:
-			raise AcceleratorError("%s has no __file__, maybe missing __init__.py?" % (package,))
+			raise AcceleratorError(f"{package} has no __file__, maybe missing __init__.py?")
 		return os.path.dirname(package_mod.__file__)
 
 
@@ -136,7 +136,7 @@ def params2optset(self, params):
 				filled_in = dict(self.params[optmethod].defaults[group])
 				filled_in.update(d)
 				for optname, optval in iteritems(filled_in):
-					optset.add('%s %s-%s %s' % (optmethod, group, optname, _reprify(optval),))
+					optset.add(f'{optmethod} {group}-{optname} {_reprify(optval)}')
 		return optset
 
 def _reprify(o):
@@ -145,15 +145,15 @@ def _reprify(o):
 	if isinstance(o, (bytes, str, int, float, bool, NoneType)):
 		return repr(o)
 	if isinstance(o, set):
-		return '[%s]' % (', '.join(map(_reprify, _sorted_set(o))),)
+		return f"[{', '.join(map(_reprify, _sorted_set(o)))}]"
 	if isinstance(o, (list, tuple)):
-		return '[%s]' % (', '.join(map(_reprify, o)),)
+		return f"[{', '.join(map(_reprify, o))}]"
 	if isinstance(o, dict):
 		assert isinstance(o, OrderedDict)
 		return '{%s}' % (', '.join('%s: %s' % (_reprify(k), _reprify(v),) for k, v in iteritems(o)),)
 	if isinstance(o, (datetime.datetime, datetime.date, datetime.time, datetime.timedelta, pathlib.Path, pathlib.PurePath)):
 		return str(o)
-	raise AcceleratorError('Unhandled %s in dependency resolution' % (type(o),))
+	raise AcceleratorError(f'Unhandled {type(o)} in dependency resolution')
 
 
 
@@ -241,13 +241,13 @@ def value2spec(value):
 		if typ:
 			return fmt % (typ,)
 	def collect(key, value, path=''):
-		path = "%s/%s" % (path, key,)
+		path = f"{path}/{key}"
 		if isinstance(value, dict):
 			for v in itervalues(value):
 				collect('*', v, path)
 			return
 		spec = value2spec(value)
-		assert res.get(path, spec) == spec, 'Method %s has incompatible types in options%s' % (method, path,)
+		assert res.get(path, spec) == spec, f'Method {method} has incompatible types in options{path}'
 		res[path] = spec
 	for k, v in iteritems(options):
 		collect(k, v)
diff --git a/accelerator/runner.py b/accelerator/runner.py
index 4ab6c39c..5969ed80 100644
--- a/accelerator/runner.py
+++ b/accelerator/runner.py
@@ -77,7 +77,7 @@ def check_picklable(desc, value):
 		return
 	except Exception as e:
 		msg = str(e)
-	raise MsgException('Unpicklable %s: %s' % (desc, msg,))
+	raise MsgException(f'Unpicklable {desc}: {msg}')
 
 def load_methods(all_packages, data):
 	from accelerator.compat import str_types, iteritems
@@ -107,7 +107,7 @@ def tar_add(name, data):
 		except Exception:
 			pass
 	for package, key in data:
-		modname = '%s.a_%s' % (package, key)
+		modname = f'{package}.a_{key}'
 		try:
 			mod, mod_filename, prefix = get_mod(modname)
 			depend_extra = []
@@ -119,7 +119,7 @@ def tar_add(name, data):
 						dep = prefix + dep
 					depend_extra.append(dep)
 				else:
-					raise MsgException('Bad depend_extra: %r' % (dep,))
+					raise MsgException(f'Bad depend_extra: {dep!r}')
 			dep_prefix = os.path.commonprefix(depend_extra + [mod_filename])
 			# commonprefix works per character (and commonpath is v3.5+)
 			dep_prefix = dep_prefix.rsplit('/', 1)[0] + '/'
@@ -149,8 +149,8 @@ def tar_add(name, data):
 				hash_extra ^= int(hashlib.sha1(data).hexdigest(), 16)
 				tar_add(dep, data)
 			for dep in (likely_deps - set(depend_extra)):
-				res_warnings.append('%s.a_%s should probably depend_extra on %s' % (package, key, dep_names[dep],))
-			res_hashes[key] = ("%040x" % (hash ^ hash_extra,),)
+				res_warnings.append(f'{package}.a_{key} should probably depend_extra on {dep_names[dep]}')
+			res_hashes[key] = (f"{hash ^ hash_extra:040x}",)
 			res_params[key] = params = DotDict()
 			# It would have been nice to be able to use ast.get_source_segment
 			def find_source(name):
@@ -187,7 +187,7 @@ def find_end(startchar, endchar):
 							end = find_end(b'['[0], b']'[0])
 							break
 					if not end:
-						print('Failed to figure out where %s is in %s' % (name, key,))
+						print(f'Failed to figure out where {name} is in {key}')
 						end = start
 					return slice(start, end)
 				except Exception:
@@ -204,23 +204,23 @@ def fmtopt(v):
 				elif isinstance(v, dict):
 					return '{%s}' % (', '.join('%s: %s' % (fmtopt(k), fmtopt(v)) for k, v in v.items()),)
 				elif isinstance(v, list):
-					return '[%s]' % (', '.join(fmtopt(v) for v in v),)
+					return f"[{', '.join((fmtopt(v) for v in v))}]"
 				elif isinstance(v, OptionEnum):
 					return '{%s}' % (', '.join(sorted(map(str, v._valid))),)
 				elif isinstance(v, OptionEnumValue):
 					return '%r {%s}' % (v, ', '.join(sorted(map(str, v._valid))),)
 				elif isinstance(v, RequiredOption):
-					return 'RequiredOption(%s%s)' % (fmtopt(v.value), ', none_ok=True' if v.none_ok else '',)
+					return f"RequiredOption({fmtopt(v.value)}{', none_ok=True' if v.none_ok else ''})"
 				elif isinstance(v, OptionDefault):
 					if v.default is None:
-						return 'OptionDefault(%s)' % (fmtopt(v.value),)
-					return 'OptionDefault(%s, default=%s)' % (fmtopt(v.value), fmtopt(v.default),)
+						return f'OptionDefault({fmtopt(v.value)})'
+					return f'OptionDefault({fmtopt(v.value)}, default={fmtopt(v.default)})'
 				else:
 					return repr(v)
 			for name, default in (('options', {},), ('datasets', (),), ('jobs', (),),):
 				params[name] = d = getattr(mod, name, default)
 				if not isinstance(d, type(default)):
-					raise MsgException("%s should be a %s" % (name, type(default).__name__,))
+					raise MsgException(f"{name} should be a {type(default).__name__}")
 				if d:
 					items = {v[0] if isinstance(v, list) else v for v in params[name]}
 					if isinstance(d, dict):
@@ -268,7 +268,7 @@ def fmtopt(v):
 				d = res_descriptions[key].get(name)
 				for item in getattr(mod, name, ()):
 					if isinstance(item, list):
-						d['[%s]' % (item[0],)] = d.pop(item[0])
+						d[f'[{item[0]}]'] = d.pop(item[0])
 			equivalent_hashes = getattr(mod, 'equivalent_hashes', ())
 			if equivalent_hashes:
 				try:
@@ -290,11 +290,11 @@ def fmtopt(v):
 				end -= 1 # to get the same hash as the old way of parsing
 				h = hashlib.sha1(src[:start])
 				h.update(src[end:])
-				verifier = "%040x" % (int(h.hexdigest(), 16) ^ hash_extra,)
+				verifier = f"{int(h.hexdigest(), 16) ^ hash_extra:040x}"
 				if verifier == k:
 					res_hashes[key] += v
 				else:
-					res_warnings.append('%s.a_%s has equivalent_hashes, but missing verifier %s' % (package, key, verifier,))
+					res_warnings.append(f'{package}.a_{key} has equivalent_hashes, but missing verifier {verifier}')
 			tar_o.close()
 			tar_fh.seek(0)
 			archives[key] = tar_fh.read()
@@ -302,7 +302,7 @@ def fmtopt(v):
 			check_picklable('description', res_descriptions[key])
 		except Exception as e:
 			if isinstance(e, MsgException):
-				print('%s: %s' % (modname, str(e),))
+				print(f'{modname}: {e!s}')
 			else:
 				print_exc(file=sys.stderr)
 			res_failed.append(modname)
diff --git a/accelerator/server.py b/accelerator/server.py
index 69b8a22e..859f163c 100644
--- a/accelerator/server.py
+++ b/accelerator/server.py
@@ -82,7 +82,7 @@ def encode_body(self, body):
 		return json_encode(body)
 
 	def handle_req(self, path, args):
-		if self.DEBUG:  print("@server.py:  Handle_req, path = \"%s\", args = %s" %( path, args ), file=sys.stderr)
+		if self.DEBUG:  print(f"@server.py:  Handle_req, path = \"{path}\", args = {args}", file=sys.stderr)
 		try:
 			self._handle_req( path, args )
 		except Exception:
@@ -185,11 +185,11 @@ def _handle_req(self, path, args):
 			else:
 				start_ix = len(jobs) - 1
 			if start_ix is None:
-				res = {'error': '%s is not a %s %s job' % (start_from, typ, method,)}
+				res = {'error': f'{start_from} is not a {typ} {method} job'}
 			else:
 				num = int(args.get('offset', 0))
 				if not jobs:
-					res = {'error': 'no %s jobs with method %s available' % (typ, method,)}
+					res = {'error': f'no {typ} jobs with method {method} available'}
 				elif 0 <= start_ix + num < len(jobs):
 					res = {'id': jobs[start_ix + num]}
 				else:
@@ -220,7 +220,7 @@ def _handle_req(self, path, args):
 				job = self.ctrl.workspaces[workdir].allocate_jobs(1)[0]
 				self.do_response(200, 'text/json', {'jobid': job})
 			else:
-				self.do_response(500, 'text/json', {'error': 'workdir %r does not exist' % (workdir,)})
+				self.do_response(500, 'text/json', {'error': f'workdir {workdir!r} does not exist'})
 
 		elif path==['submit']:
 			if self.ctrl.broken:
@@ -383,7 +383,7 @@ def run(self):
 		except Exception:
 			traceback.print_exc(file=sys.stderr)
 		finally:
-			print("Thread %r died. That's bad." % (self.name,))
+			print(f"Thread {self.name!r} died. That's bad.")
 			exitfunction(DeadlyThread)
 
 
@@ -406,7 +406,7 @@ def check_socket(fn):
 		except OSError:
 			pass
 		return
-	raise Exception("Socket %s already listening" % (fn,))
+	raise Exception(f"Socket {fn} already listening")
 
 def siginfo(sig, frame):
 	print_status_stacks()
@@ -519,5 +519,5 @@ def buf_up(fh, opt):
 		print("%17s: %s%s" % (n, v, extra,))
 	print()
 
-	print("Serving on %s\n" % (config.listen,), file=sys.stderr)
+	print(f"Serving on {config.listen}\n", file=sys.stderr)
 	server.serve_forever()
diff --git a/accelerator/setupfile.py b/accelerator/setupfile.py
index 28089357..397a7636 100644
--- a/accelerator/setupfile.py
+++ b/accelerator/setupfile.py
@@ -62,7 +62,7 @@ def load_setup(jobid):
 	try:
 		d = json_load('setup.json', jobid)
 	except IOError:
-		raise NoSuchJobError('Job %r not found' % (jobid,))
+		raise NoSuchJobError(f'Job {jobid!r} not found')
 	version = d.version
 	if version == 1:
 		d.jobs = d.pop('jobids')
@@ -127,7 +127,7 @@ def copy_json_safe(src):
 		elif isinstance(src, timedelta):
 			return src.total_seconds()
 		else:
-			assert isinstance(src, (str, int, float, bool)) or src is None, "%s not supported in data" % (type(src),)
+			assert isinstance(src, (str, int, float, bool)) or src is None, f"{type(src)} not supported in data"
 			return src
 
 def encode_setup(data, sort_keys=True, as_str=False):
@@ -162,7 +162,7 @@ def _encode_with_compact(data, compact_keys, extra_indent=0, separator='\n', spe
 				fmted = _encode_with_compact(d, ('analysis', 'per_slice',), 1, '')
 			else:
 				fmted = dumps(data[k])
-			compact.append('    "%s": %s,' % (k, fmted,))
+			compact.append(f'    "{k}": {fmted},')
 			del data[k]
 	for k in special_keys:
 		if k in data:
diff --git a/accelerator/shell/__init__.py b/accelerator/shell/__init__.py
index 4e6679ab..82fe09cb 100644
--- a/accelerator/shell/__init__.py
+++ b/accelerator/shell/__init__.py
@@ -79,13 +79,13 @@ def load_some_cfg(basedir='.', all=False):
 				# As long as we find at least one we're happy.
 				pass
 		if not found_any:
-			raise UserError("Could not find 'accelerator*.conf' in %r or any of its parents." % (basedir,))
+			raise UserError(f"Could not find 'accelerator*.conf' in {basedir!r} or any of its parents.")
 		cfg.config_filename = None
 	else:
 		try:
 			fn = next(cfgs)
 		except StopIteration:
-			raise UserError("Could not find 'accelerator.conf' in %r or any of its parents." % (basedir,))
+			raise UserError(f"Could not find 'accelerator.conf' in {basedir!r} or any of its parents.")
 		load_cfg(fn)
 
 def load_cfg(fn):
@@ -97,7 +97,7 @@ def load_cfg(fn):
 	cfg = load_config(fn)
 	for k, v in cfg.workdirs.items():
 		if WORKDIRS.get(k, v) != v:
-			print("WARNING: %s overrides workdir %s" % (fn, k,), file=sys.stderr)
+			print(f"WARNING: {fn} overrides workdir {k}", file=sys.stderr)
 		WORKDIRS[k] = v
 	return cfg
 
@@ -269,7 +269,7 @@ def cmd_version(argv, as_command=True):
 			py_version = sys.implementation.name
 			suffix = ' (%s)' % (suffix.split('\n')[0].strip(),)
 			impl_version = '.'.join(map(str, sys.implementation.version))
-			py_version = '%s %s' % (py_version, impl_version,)
+			py_version = f'{py_version} {impl_version}'
 		except Exception:
 			pass
 		print('Running on ' + py_version + suffix)
@@ -337,7 +337,7 @@ def read(fn, seen_fns=(), must_exist=False):
 			for include in shlex.split(include):
 				include = join(dirname(fn), expanduser(include))
 				if include in seen_fns:
-					raise Exception('Config include loop: %r goes back to %r' % (fn, include,))
+					raise Exception(f'Config include loop: {fn!r} goes back to {include!r}')
 				read(include, seen_fns, True)
 		# Append this file after the included files, so this file takes priority.
 		all_cfg.append((fn, contents))
@@ -360,7 +360,7 @@ def chopline(description, max_len):
 				if len(description) + len(part) + 1 > max_len:
 					break
 				if description:
-					description = '%s %s' % (description, part,)
+					description = f'{description} {part}'
 				else:
 					description = part
 			description += colour.faint(ddot)
@@ -408,7 +408,7 @@ def expand_env(words, alias):
 				try:
 					expanded = shlex.split(environ[k])
 				except ValueError as e:
-					raise ValueError('Failed to expand alias %s (%s -> %r): %s' % (alias, word, environ[k], e,))
+					raise ValueError(f'Failed to expand alias {alias} ({word} -> {environ[k]!r}): {e}')
 				for word in expanded:
 					yield word
 		else:
@@ -423,7 +423,7 @@ def expand_aliases(main_argv, argv):
 		try:
 			expanded = shlex.split(aliases[alias])
 		except ValueError as e:
-			raise ValueError('Failed to expand alias %s (%r): %s' % (argv[0], aliases[argv[0]], e,))
+			raise ValueError(f'Failed to expand alias {argv[0]} ({aliases[argv[0]]!r}): {e}')
 		expanded = list(expand_env(expanded, alias))
 		more_main_argv, argv = split_args(expanded + argv[1:])
 		main_argv.extend(more_main_argv)
@@ -431,7 +431,7 @@ def expand_aliases(main_argv, argv):
 			break
 		used_aliases.append(alias)
 		if alias in used_aliases[:-1]:
-			raise ValueError('Alias loop: %r' % (used_aliases,))
+			raise ValueError(f'Alias loop: {used_aliases!r}')
 
 	while argv and argv[0] == 'noalias':
 		argv.pop(0)
@@ -534,7 +534,7 @@ def main():
 		parser.print_help(file=sys.stderr)
 		if args.command is not None:
 			print(file=sys.stderr)
-			print('Unknown command "%s"' % (args.command,), file=sys.stderr)
+			print(f'Unknown command "{args.command}"', file=sys.stderr)
 		sys.exit(2)
 	config_fn = args.config
 	if args.command in ('init', 'intro', 'version', 'alias',):
@@ -543,7 +543,7 @@ def main():
 	debug_cmd = getattr(cmd, 'is_debug', False)
 	try:
 		setup(config_fn, debug_cmd)
-		argv.insert(0, '%s %s' % (basename(sys.argv[0]), args.command,))
+		argv.insert(0, f'{basename(sys.argv[0])} {args.command}')
 		return cmd(argv)
 	except UserError as e:
 		print(e, file=sys.stderr)
diff --git a/accelerator/shell/ds.py b/accelerator/shell/ds.py
index b706971a..3502d086 100644
--- a/accelerator/shell/ds.py
+++ b/accelerator/shell/ds.py
@@ -72,7 +72,7 @@ def format_location(loc):
 	is_local, ds, colname = loc
 	if is_local:
 		return 'local'
-	return '%s in %s' % (quote(colname), ds.quoted,)
+	return f'{quote(colname)} in {ds.quoted}'
 
 def typed_from(ds, loc):
 	if not loc:
@@ -85,7 +85,7 @@ def typed_from(ds, loc):
 	res = 'typed from ' + format_location((False, src_ds, colname))
 	orig_loc = original_location(src_ds, colname)
 	if orig_loc and not orig_loc[0]:
-		return '%s, originally %s' % (res, format_location(orig_loc))
+		return f'{res}, originally {format_location(orig_loc)}'
 	else:
 		return res
 
@@ -116,7 +116,7 @@ def finish(badinput):
 		if badinput and not args.suppress_errors:
 			print('Error, failed to resolve datasets:', file=sys.stderr)
 			for n, e in badinput:
-				print('    %r: %s' % (n, e,), file=sys.stderr)
+				print(f'    {n!r}: {e}', file=sys.stderr)
 			exit(1)
 		exit()
 
@@ -133,7 +133,7 @@ def finish(badinput):
 				badinput.append((n, e))
 				dsvec = None
 			if dsvec:
-				print('%s' % (dsvec[0].job,))
+				print(f'{dsvec[0].job}')
 				v = []
 				for ds in dsvec:
 					if args.chainedlist:
@@ -212,8 +212,8 @@ def prettyminmax(n):
 					except Exception:
 						# source job might be deleted
 						pass
-			print("    {0} columns".format(fmt_num(len(ds.columns))))
-		print("    {0} lines".format(fmt_num(sum(ds.lines))))
+			print(f"    {fmt_num(len(ds.columns))} columns")
+		print(f"    {fmt_num(sum(ds.lines))} lines")
 
 		if ds.previous or args.chain:
 			chain = ds.chain()
@@ -223,15 +223,15 @@ def prettyminmax(n):
 				if in_job == len(chain):
 					in_job = ' (all within job)'
 				else:
-					in_job = ' ({0} within job)'.format(fmt_num(in_job))
+					in_job = f' ({fmt_num(in_job)} within job)'
 			else:
 				in_job = ''
-			print("    {0} length {1}{2}, from {3} to {4}".format(full_name, fmt_num(len(chain)), in_job, chain[0], chain[-1]))
+			print(f"    {full_name} length {fmt_num(len(chain))}{in_job}, from {chain[0]} to {chain[-1]}")
 			if args.non_empty_chain:
 				chain = [ds for ds in chain if sum(ds.lines)]
-				print("    Filtered chain length {0}".format(fmt_num(len(chain))))
+				print(f"    Filtered chain length {fmt_num(len(chain))}")
 			if args.chain:
-				data = tuple((ix, "%s/%s" % (x.job, x.name), fmt_num(sum(x.lines))) for ix, x in enumerate(chain))
+				data = tuple((ix, f"{x.job}/{x.name}", fmt_num(sum(x.lines))) for ix, x in enumerate(chain))
 				max_n, max_l = colwidth(x[1:] for x in data)
 				template = "{0:3}: {1:%d} ({2:>%d})" % (max_n, max_l)
 				printcolwise(data, template, lambda x: (x[0], x[1], x[2]), minrows=8, indent=8)
@@ -254,6 +254,6 @@ def prettyminmax(n):
 			print("    Max to average ratio: " + locale.format_string("%2.3f", (max(x[2] for x in data) / ((s or 1e20) / len(data)),) ))
 
 		if ds.previous:
-			print("    {0} total lines in chain".format(fmt_num(sum(sum(ds.lines) for ds in chain))))
+			print(f"    {fmt_num(sum((sum(ds.lines) for ds in chain)))} total lines in chain")
 
 	finish(badinput)
diff --git a/accelerator/shell/gc.py b/accelerator/shell/gc.py
index 2154e94f..06ed9133 100644
--- a/accelerator/shell/gc.py
+++ b/accelerator/shell/gc.py
@@ -48,8 +48,8 @@ def candidate(jid):
 		print("Nothing to do.")
 		return 0
 	if args.dry_run:
-		print("Would have deleted %d jobs" % (len(to_delete),))
+		print(f"Would have deleted {len(to_delete)} jobs")
 		return 0
-	print("Deleting %d jobs" % (len(to_delete),))
+	print(f"Deleting {len(to_delete)} jobs")
 	for job in to_delete:
 		shutil.rmtree(job.path)
diff --git a/accelerator/shell/grep.py b/accelerator/shell/grep.py
index c0208faf..2337733c 100644
--- a/accelerator/shell/grep.py
+++ b/accelerator/shell/grep.py
@@ -76,7 +76,7 @@ def number_or_None(obj):
 def number_or_error(obj):
 	number = number_or_None(obj)
 	if number is None:
-		raise re.error('%r is not a valid not a number' % (obj,))
+		raise re.error(f'{obj!r} is not a valid not a number')
 	return number
 
 def splitprefix(s, prefixes):
@@ -177,12 +177,12 @@ def __call__(self, parser, namespace, values, option_string=None):
 				else:
 					name = next(unnamed)
 				if name not in names:
-					raise ArgumentError(self, 'unknown field %r' % (name,))
+					raise ArgumentError(self, f'unknown field {name!r}')
 				name = names[name]
 				try:
 					value = int(value)
 				except ValueError:
-					raise ArgumentError(self, 'invalid int value for %s: %r' % (name, value,))
+					raise ArgumentError(self, f'invalid int value for {name}: {value!r}')
 				if value < min_value[name] or value > 9999:
 					raise ArgumentError(self, 'invalid value for %s: %d' % (name, value,))
 				tab_length[name] = value
@@ -314,7 +314,7 @@ def __call__(self, parser, namespace, values, option_string=None):
 			else:
 				patterns.append(re.compile(pattern, re_flags))
 		except re.error as e:
-			print("Bad pattern %r:\n%s" % (pattern, e,), file=sys.stderr)
+			print(f"Bad pattern {pattern!r}:\n{e}", file=sys.stderr)
 			return 1
 
 	grep_columns = set(args.grep or ())
@@ -385,7 +385,7 @@ def columns_for_ds(ds, columns=columns, not_columns=not_columns):
 			for ds in datasets:
 				missing = need_cols - set(ds.columns)
 				if missing:
-					print('ERROR: %s does not have columns %r' % (ds, missing,), file=sys.stderr)
+					print(f'ERROR: {ds} does not have columns {missing!r}', file=sys.stderr)
 					bad = True
 			if bad:
 				return 1
@@ -587,27 +587,27 @@ def show(sig, frame):
 					if ds_ix == len(datasets):
 						msg = 'DONE'
 					else:
-						msg = '{0:d}% of {1:n} lines'.format(round(p * 100), total_lines_per_slice_at_ds[-1][sliceno])
+						msg = f'{round(p * 100):d}% of {total_lines_per_slice_at_ds[-1][sliceno]:n} lines'
 						if show_ds:
-							msg = '%s (in %s)' % (msg, datasets[ds_ix].quoted,)
+							msg = f'{msg} (in {datasets[ds_ix].quoted})'
 					msg = '%9d: %s' % (sliceno, msg,)
 					if p < bad_cutoff:
 						msg = colour(msg, 'grep/infohighlight')
 					else:
 						msg = colour(msg, 'grep/info')
 					write(2, msg.encode('utf-8') + b'\n')
-			msg = '{0:d}% of {1:n} lines'.format(round(progress_total * 100), total_lines)
+			msg = f'{round(progress_total * 100):d}% of {total_lines:n} lines'
 			if len(datasets) > 1:
 				min_ds = min(ds_ixes)
 				max_ds = max(ds_ixes)
 				if min_ds < len(datasets):
 					ds_name = datasets[min_ds].quoted
 					extra = '' if min_ds == max_ds else ' ++'
-					msg = '%s (in %s%s)' % (msg, ds_name, extra,)
+					msg = f'{msg} (in {ds_name}{extra})'
 			worst = min(progress_fraction)
 			if worst < bad_cutoff:
 				msg = '%s, worst %d%%' % (msg, round(worst * 100),)
-			msg = colour('  SUMMARY: %s' % (msg,), 'grep/info')
+			msg = colour(f'  SUMMARY: {msg}', 'grep/info')
 			write(2, msg.encode('utf-8') + b'\n')
 		for signame in ('SIGINFO', 'SIGUSR1'):
 			if hasattr(signal, signame):
@@ -1329,7 +1329,7 @@ def gen_headers(headers):
 			unique_columns = tuple(col for col in columns_for_ds(ds) if unique_filter(col))
 			if check_unique_columns_existance and len(unique_columns) != len(args.unique):
 				missing = args.unique - set(unique_columns)
-				print('ERROR: %s does not have columns %r' % (ds.quoted, missing,), file=sys.stderr)
+				print(f'ERROR: {ds.quoted} does not have columns {missing!r}', file=sys.stderr)
 				bad = True
 			if unique_columns not in unique_columns2ix:
 				unique_columns2ix[unique_columns] = unique_columns_ix
diff --git a/accelerator/shell/hist.py b/accelerator/shell/hist.py
index ea351a5b..aaa83765 100644
--- a/accelerator/shell/hist.py
+++ b/accelerator/shell/hist.py
@@ -164,7 +164,7 @@ def main(argv, cfg):
 	for ds in chain:
 		for col in args.column:
 			if col not in ds.columns:
-				print("Dataset %s does not have column %s." % (ds.quoted, col,), file=sys.stderr)
+				print(f"Dataset {ds.quoted} does not have column {col}.", file=sys.stderr)
 				ok = False
 	if not ok:
 		return 1
@@ -264,12 +264,12 @@ def name(ix):
 					if a == b:
 						return fmt_num(a)
 					else:
-						return '%s - %s' % (fmt_num(a), fmt_num(b))
+						return f'{fmt_num(a)} - {fmt_num(b)}'
 			else:
 				def name(ix):
 					a = step * ix + low
 					b = step * (ix + 1) + low
-					return '%s - %s' % (fmt_num(a), fmt_num(b))
+					return f'{fmt_num(a)} - {fmt_num(b)}'
 			bin_names = [name(ix) for ix in range(args.max_count)]
 
 	def collect_hist(hist, part):
diff --git a/accelerator/shell/init.py b/accelerator/shell/init.py
index 3f776612..f14f7ffe 100644
--- a/accelerator/shell/init.py
+++ b/accelerator/shell/init.py
@@ -197,7 +197,7 @@ def add_argument(name, default=None, help='', **kw):
 					if default.lower() == 'true':
 						bool_fallbacks.add(cfg_name.replace('-', '_'))
 					elif default.lower() != 'false':
-						raise UserError("Configuration init.%s must be either true or false, not %r." % (cfg_name, default,))
+						raise UserError(f"Configuration init.{cfg_name} must be either true or false, not {default!r}.")
 					default = None
 				elif 'type' in kw:
 					default = kw['type'](default)
@@ -311,7 +311,7 @@ def slice_count(workdir):
 
 	if not options.force:
 		if exists(options.directory) and set(listdir(options.directory)) - {'venv', '.venv'}:
-			raise UserError('Directory %r is not empty.' % (options.directory,))
+			raise UserError(f'Directory {options.directory!r} is not empty.')
 		def plausible_jobdir(n):
 			parts = n.rsplit('-', 1)
 			return len(parts) == 2 and parts[0] == options.name and parts[1].isnumeric()
@@ -322,7 +322,7 @@ def plausible_jobdir(n):
 				if workdir_slices not in (None, options.slices):
 					raise UserError('Workdir %r has %d slices, refusing to continue with %d slices' % (workdir, workdir_slices, options.slices,))
 		if exists(first_workdir_path) and any(map(plausible_jobdir, listdir(first_workdir_path))):
-			raise UserError('Workdir %r already has jobs in it.' % (first_workdir_path,))
+			raise UserError(f'Workdir {first_workdir_path!r} already has jobs in it.')
 
 	if not exists(options.directory):
 		makedirs(options.directory)
@@ -357,7 +357,7 @@ def plausible_jobdir(n):
 		examples = 'examples'
 	else:
 		examples = '# accelerator.examples'
-	all_workdirs = ['%s %s' % (shell_quote(name), shell_quote(path),) for name, path in workdirs]
+	all_workdirs = [f'{shell_quote(name)} {shell_quote(path)}' for name, path in workdirs]
 	with open('accelerator.conf', 'w') as fh:
 		fh.write(config_template.format(
 			name=shell_quote(options.name),
diff --git a/accelerator/shell/job.py b/accelerator/shell/job.py
index 3f93764b..1fa301bf 100644
--- a/accelerator/shell/job.py
+++ b/accelerator/shell/job.py
@@ -46,16 +46,16 @@ def show(url, job, verbose, show_output):
 		print(encode_setup(setup, as_str=True))
 	else:
 		starttime = datetime.fromtimestamp(setup.starttime).replace(microsecond=0)
-		hdr = '%s (%s) at %s' % (job, job.method, starttime,)
+		hdr = f'{job} ({job.method}) at {starttime}'
 		if 'exectime' in setup:
-			hdr = '%s in %s' % (hdr, fmttime(setup.exectime.total),)
+			hdr = f'{hdr} in {fmttime(setup.exectime.total)}'
 		print(colour(hdr, 'job/header'))
 		if job.is_build:
 			print(colour('  build job', 'job/highlight'))
 		if job.parent:
-			built_from = "  built from %s (%s)" % (job.parent, job.parent.method,)
+			built_from = f"  built from {job.parent} ({job.parent.method})"
 			if job.build_job and job.parent != job.build_job:
-				built_from = "%s, build job %s (%s)" % (built_from, job.build_job, job.build_job.method,)
+				built_from = f"{built_from}, build job {job.build_job} ({job.build_job.method})"
 			print(colour(built_from, 'job/highlight'))
 		things = []
 		def opt_thing(name):
@@ -71,13 +71,13 @@ def opt_thing(name):
 		opt_thing('datasets')
 		opt_thing('jobs')
 		for k, v in things:
-			print('    %s: %s' % (k, v,))
+			print(f'    {k}: {v}')
 	def list_of_things(name, things):
 		total = len(things)
 		if total > 5 and not verbose:
 			things = things[:3]
 		print()
-		print(colour('%s:' % (name,), 'job/header'))
+		print(colour(f'{name}:', 'job/header'))
 		for thing in things:
 			print('   ', thing)
 		if total > len(things):
@@ -127,7 +127,7 @@ def show_source(job, pattern='*'):
 		members = [info for info in all_members if fnmatch(info.path, pattern)]
 		if not members:
 			if pattern:
-				print(colour('No sources matching %r in %s.' % (pattern, job,), 'job/warning'), file=sys.stderr)
+				print(colour(f'No sources matching {pattern!r} in {job}.', 'job/warning'), file=sys.stderr)
 				fh = sys.stderr
 				res = 1
 			else:
@@ -163,7 +163,7 @@ def show_file(job, pattern):
 	if not files:
 		if pattern:
 			fh = sys.stderr
-			print(colour('No files matching %r in %s.' % (pattern, job,), 'job/warning'), file=fh)
+			print(colour(f'No files matching {pattern!r} in {job}.', 'job/warning'), file=fh)
 			res = 1
 		else:
 			fh = sys.stdout
@@ -261,6 +261,6 @@ def main(argv, cfg):
 			if isinstance(e, OSError) and e.errno == errno.EPIPE:
 				raise
 			print_exc(file=sys.stderr)
-			print("Failed to show %r" % (path,), file=sys.stderr)
+			print(f"Failed to show {path!r}", file=sys.stderr)
 			res = 1
 	return res
diff --git a/accelerator/shell/lined.py b/accelerator/shell/lined.py
index 1015efd7..02849f92 100644
--- a/accelerator/shell/lined.py
+++ b/accelerator/shell/lined.py
@@ -43,7 +43,7 @@ def split_colour(spec):
 		elif 40 <= code <= 48 or 100 <= code <= 107:
 			target = bg
 		elif code not in (39, 49):
-			print("Sorry, %s can only use colours, not attributes" % (spec,), file=sys.stderr)
+			print(f"Sorry, {spec} can only use colours, not attributes", file=sys.stderr)
 			sys.exit(1)
 		target.append(part)
 	return ';'.join(fg), ';'.join(bg)
@@ -96,7 +96,7 @@ def close(self):
 		os.close(self.saved_stdout)
 		self.process.join()
 		if self.process.exitcode and self.process.exitcode != _RC_EPIPE:
-			raise Exception('Liner process exited with %s' % (self.process.exitcode,))
+			raise Exception(f'Liner process exited with {self.process.exitcode}')
 
 
 def enable_lines(colour_prefix, lined=True, decode_lines=False, max_count=None, after=0):
@@ -169,11 +169,11 @@ def decode_part(part):
 				todo = iter(line)
 				data = []
 				if line_fg and line_bg:
-					data.append('\x1b[%s;%sm' % (line_fg, line_bg,))
+					data.append(f'\x1b[{line_fg};{line_bg}m')
 				elif line_bg:
-					data.append('\x1b[%sm' % (line_bg,))
+					data.append(f'\x1b[{line_bg}m')
 				elif line_fg:
-					data.append('\x1b[%sm' % (line_fg,))
+					data.append(f'\x1b[{line_fg}m')
 				if line_bg and not decode_lines:
 					data.append('\x1b[K') # try to fill the line with bg (if terminal does BCE)
 				for c in todo:
diff --git a/accelerator/shell/method.py b/accelerator/shell/method.py
index ee6e5bc8..f5a0728d 100644
--- a/accelerator/shell/method.py
+++ b/accelerator/shell/method.py
@@ -34,7 +34,7 @@ def main(argv, cfg):
 		for name in args.method:
 			if name in methods:
 				data = methods[name]
-				print('%s.%s:' % (data.package, name,))
+				print(f'{data.package}.{name}:')
 				if data.description.text:
 					for line in data.description.text.split('\n'):
 						if line:
@@ -43,11 +43,11 @@ def main(argv, cfg):
 							print()
 					print()
 				if cfg.get('interpreters'):
-					print('Runs on <%s> %s' % (data.version, data.description.interpreter,))
+					print(f'Runs on <{data.version}> {data.description.interpreter}')
 					print()
 				for k in ('datasets', 'jobs',):
 					if data.description.get(k):
-						print('%s:' % (k,))
+						print(f'{k}:')
 						klen = max(len(k) for k in data.description[k])
 						template = '  %%-%ds # %%s' % (klen,)
 						for k, v in data.description[k].items():
@@ -80,13 +80,13 @@ def main(argv, cfg):
 						else:
 							print(first)
 			else:
-				print('Method %r not found' % (name,))
+				print(f'Method {name!r} not found')
 	else:
 		by_package = defaultdict(list)
 		for name, data in sorted(methods.items()):
 			by_package[data.package].append(name)
 		by_package.pop('accelerator.test_methods', None)
 		for package, names in sorted(by_package.items()):
-			print('%s:' % (package,))
+			print(f'{package}:')
 			items = [(name, methods[name].description.text) for name in names]
 			printdesc(items, columns, 'method')
diff --git a/accelerator/shell/parser.py b/accelerator/shell/parser.py
index bb1cad5d..2b78ad98 100644
--- a/accelerator/shell/parser.py
+++ b/accelerator/shell/parser.py
@@ -71,7 +71,7 @@ def split_tildes(n, allow_empty=False, extended=False):
 	return n, lst
 
 def method2job(cfg, method, **kw):
-	url ='%s/method2job/%s?%s' % (cfg.url, url_quote(method), urlencode(kw))
+	url =f'{cfg.url}/method2job/{url_quote(method)}?{urlencode(kw)}'
 	found = call(url)
 	if 'error' in found:
 		raise JobNotFound(found.error)
@@ -144,30 +144,30 @@ def split(n, what):
 			if n in ('jobs', 'datasets'):
 				k = n
 				if current or tildes:
-					raise JobNotFound("Don't use !~+<>^ on .%s, put after .%s.foo(HERE)." % (k, k))
+					raise JobNotFound(f"Don't use !~+<>^ on .{k}, put after .{k}.foo(HERE).")
 				try:
 					n = next(dotted)
 				except StopIteration:
-					raise JobNotFound("%s.%s.what?" % (job, k,))
+					raise JobNotFound(f"{job}.{k}.what?")
 				n, current, tildes = split(n, k)
 			elif n in p.jobs and n in p.datasets:
-				raise JobNotFound("Job %s (%s) has %s in both .jobs and .datasets, please specify." % (job, job.method, n,))
+				raise JobNotFound(f"Job {job} ({job.method}) has {n} in both .jobs and .datasets, please specify.")
 			if k:
 				if n not in p[k]:
-					raise JobNotFound("Job %s (%s) does not have a %r." % (job, job.method, k + '.' + n,))
+					raise JobNotFound(f"Job {job} ({job.method}) does not have a {k + '.' + n!r}.")
 			else:
 				if n in p.jobs:
 					k = 'jobs'
 				elif n in p.datasets:
 					k = 'datasets'
 				else:
-					raise JobNotFound("Job %s (%s) does not have a %r." % (job, job.method, n,))
+					raise JobNotFound(f"Job {job} ({job.method}) does not have a {n!r}.")
 			if not p[k][n]:
-				raise JobNotFound("%s.%s.%s is None" % (job, k, n,))
+				raise JobNotFound(f"{job}.{k}.{n} is None")
 			job = p[k][n]
 			if isinstance(job, list):
 				if len(job) != 1:
-					raise JobNotFound("Job %s (%s) has %d %s in %r." % (job, job.method, len(job), k, n,))
+					raise JobNotFound(f"Job {job} ({job.method}) has {len(job)} {k} in {n!r}.")
 				job = job[0]
 			if isinstance(job, Dataset):
 				ds = job
@@ -196,9 +196,9 @@ def _name2job_do_tildes(cfg, job, current, tildes):
 		elif char == '>':
 			job = Job._create(job.workdir, job.number + count)
 		else:
-			raise Exception("BUG: split_tildes should not give %r as a char" % (char,))
+			raise Exception(f"BUG: split_tildes should not give {char!r} as a char")
 	if not exists(job.filename('setup.json')):
-		raise JobNotFound('Job resolved to %r but that job does not exist' % (job,))
+		raise JobNotFound(f'Job resolved to {job!r} but that job does not exist')
 	return job
 
 def _name2job(cfg, n, current):
@@ -226,12 +226,12 @@ def _name2job(cfg, n, current):
 			print(e, file=sys.stderr)
 			urdres = None
 		if not urdres:
-			raise JobNotFound('urd list %r not found' % (a[0],))
+			raise JobNotFound(f'urd list {a[0]!r} not found')
 		from accelerator.build import JobList
 		joblist = JobList(Job(e[1], e[0]) for e in urdres.joblist)
 		res = joblist.get(entry)
 		if not res:
-			raise JobNotFound('%r not found in %s' % (entry, path,))
+			raise JobNotFound(f'{entry!r} not found in {path}')
 		return res
 	if re.match(r'[^/]+-\d+$', n):
 		# Looks like a jobid
@@ -241,12 +241,12 @@ def _name2job(cfg, n, current):
 		# Looks like workdir-LATEST
 		wd = m.group(1)
 		if wd not in WORKDIRS:
-			raise NoSuchWorkdirError('Not a valid workdir: "%s"' % (wd,))
+			raise NoSuchWorkdirError(f'Not a valid workdir: "{wd}"')
 		path = join(WORKDIRS[wd], n)
 		try:
 			n = readlink(path)
 		except OSError as e:
-			raise JobNotFound('Failed to read %s: %s' % (path, e,))
+			raise JobNotFound(f'Failed to read {path}: {e}')
 		return Job(n)
 	if n not in ('.', '..') and '/' not in n:
 		# Must be a method then
@@ -256,10 +256,10 @@ def _name2job(cfg, n, current):
 		path, jid = split(realpath(n))
 		job = Job(jid)
 		if WORKDIRS.get(job.workdir, path) != path:
-			print("### Overriding workdir %s to %s" % (job.workdir, path,))
+			print(f"### Overriding workdir {job.workdir} to {path}")
 		WORKDIRS[job.workdir] = path
 		return job
-	raise JobNotFound("Don't know what to do with %r." % (n,))
+	raise JobNotFound(f"Don't know what to do with {n!r}.")
 
 def split_ds_dir(n):
 	"""try to split a path at the jid/ds boundary"""
@@ -276,7 +276,7 @@ def split_ds_dir(n):
 		n, bit = n.rsplit('/', 1)
 		name_bits.append(bit)
 	if not n:
-		raise JobNotFound('No setup.json found in %r' % (orig_n,))
+		raise JobNotFound(f'No setup.json found in {orig_n!r}')
 	if not name_bits:
 		name_bits = ['default']
 	return n, '/'.join(reversed(name_bits))
diff --git a/accelerator/shell/script.py b/accelerator/shell/script.py
index 80eaff72..a9aa2013 100644
--- a/accelerator/shell/script.py
+++ b/accelerator/shell/script.py
@@ -57,7 +57,7 @@ def main(argv, cfg):
 				try:
 					module = import_module(modname)
 				except Exception as e:
-					print(colour('%s: %s' % (item, e,), 'script/warning'), file=sys.stderr)
+					print(colour(f'{item}: {e}', 'script/warning'), file=sys.stderr)
 					continue
 				scripts.append((name, getattr(module, 'description', '')))
 
diff --git a/accelerator/shell/sherlock.py b/accelerator/shell/sherlock.py
index 1e04798c..6ad9ed87 100644
--- a/accelerator/shell/sherlock.py
+++ b/accelerator/shell/sherlock.py
@@ -37,7 +37,7 @@ def validate(data):
 		job = None
 	if job:
 		if job.path != data.job:
-			warnings.append("path mismatch (%r != %r)" % (job.path, data.job,))
+			warnings.append(f"path mismatch ({job.path!r} != {data.job!r})")
 	else:
 		warnings.append("unknown job")
 	h = b64hash_setup(data.job + '/setup.json')
@@ -85,14 +85,14 @@ def main(argv, cfg):
 					print(prefix + colour('decoding error', 'sherlock/warning'), file=sys.stderr)
 					continue
 				if args.verbose:
-					print('%s%s' % (prefix, data.job,), end='')
+					print(f'{prefix}{data.job}', end='')
 				else:
-					print('%s%s' % (prefix, data.job.rsplit('/', 1)[-1],), end='')
+					print(f"{prefix}{data.job.rsplit('/', 1)[-1]}", end='')
 				warnings = validate(data)
 				if warnings:
 					print(' ' + colour(', '.join(warnings), 'sherlock/warning'), end='')
 				if args.verbose:
 					ts = datetime.fromtimestamp(data.time)
-					print(' (%s at %s on %s)' % (data.method, ts, data.host), end='')
+					print(f' ({data.method} at {ts} on {data.host})', end='')
 				print()
 	return res
diff --git a/accelerator/shell/status.py b/accelerator/shell/status.py
index 8470e872..6a6d9365 100644
--- a/accelerator/shell/status.py
+++ b/accelerator/shell/status.py
@@ -38,13 +38,13 @@ def main(argv, cfg):
 			error = call(cfg.url + '/last_error')
 			t = datetime.fromtimestamp(error.time).replace(microsecond=0)
 			print()
-			print('Last error at %s:' % (t,))
+			print(f'Last error at {t}:')
 			for jobid, method, status in error.last_error:
 				e = JobError(Job(jobid, method), method, status)
 				print(e.format_msg(), file=sys.stderr)
 	else:
 		if args.short:
 			t = fmttime(status.report_t - status.current[0], True)
-			print('%s (%s)' % (status.current[1], t))
+			print(f'{status.current[1]} ({t})')
 		else:
 			print_status_stacks(status.status_stacks)
diff --git a/accelerator/shell/urd.py b/accelerator/shell/urd.py
index 8db1c889..51edfb4d 100644
--- a/accelerator/shell/urd.py
+++ b/accelerator/shell/urd.py
@@ -87,7 +87,7 @@ def urd_get(path):
 		if path.startswith(':'):
 			a = path[1:].split(':', 1)
 			if len(a) == 1:
-				print('%r should have two or no :' % (path,), file=sys.stderr)
+				print(f'{path!r} should have two or no :', file=sys.stderr)
 				return None, None
 			path = a[0]
 			try:
@@ -99,10 +99,10 @@ def urd_get(path):
 			entry = tildes = None
 		path = resolve_path_part(path)
 		if len(path) != 3 and tildes:
-			print("path %r isn't walkable (~^)" % ('/'.join(path),), file=sys.stderr)
+			print(f"path {'/'.join(path)!r} isn't walkable (~^)", file=sys.stderr)
 			return None, None
 		if len(path) != 3 and entry is not None:
-			print("path %r doesn't take an entry (%r)" % ('/'.join(path), entry,), file=sys.stderr)
+			print(f"path {'/'.join(path)!r} doesn't take an entry ({entry!r})", file=sys.stderr)
 			return None, None
 		try:
 			res = urd_call_w_tildes(cfg, '/'.join(path), tildes)
@@ -139,7 +139,7 @@ def fmt_caption(path, caption, indent):
 		return joblist.get(entry, '')
 	if res['deps']:
 		deps = sorted(
-			('%s/%s' % (k, v['timestamp'],), v['caption'],)
+			(f"{k}/{v['timestamp']}", v['caption'],)
 			for k, v in res['deps'].items()
 		)
 		if len(deps) > 1:
diff --git a/accelerator/shell/workdir.py b/accelerator/shell/workdir.py
index 79212cdb..dc1f8a93 100644
--- a/accelerator/shell/workdir.py
+++ b/accelerator/shell/workdir.py
@@ -72,7 +72,7 @@ def workdir_jids(cfg, name):
 			if wd == name and num.isdigit():
 				jidlist.append(int(num))
 	jidlist.sort()
-	return ['%s-%s' % (name, jid,) for jid in jidlist]
+	return [f'{name}-{jid}' for jid in jidlist]
 
 def main(argv, cfg):
 	usage = "%(prog)s [-p] [-a | [workdir [workdir [...]]]"
diff --git a/accelerator/standard_methods/a_csvexport.py b/accelerator/standard_methods/a_csvexport.py
index 5c59979b..1b7a890d 100644
--- a/accelerator/standard_methods/a_csvexport.py
+++ b/accelerator/standard_methods/a_csvexport.py
@@ -95,7 +95,7 @@ def csvexport(sliceno, filename, labelsonfirstline):
 	if options.none_as:
 		if isinstance(options.none_as, dict):
 			bad_none = set(options.none_as) - set(options.labels)
-			assert not bad_none, 'Unknown labels in none_as: %r' % (bad_none,)
+			assert not bad_none, f'Unknown labels in none_as: {bad_none!r}'
 		else:
 			assert isinstance(options.none_as, str), "What did you pass as none_as?"
 	def resolve_none(label, col):
diff --git a/accelerator/standard_methods/a_csvimport.py b/accelerator/standard_methods/a_csvimport.py
index bea51d16..64d27fd0 100644
--- a/accelerator/standard_methods/a_csvimport.py
+++ b/accelerator/standard_methods/a_csvimport.py
@@ -88,7 +88,7 @@ def reader_status(status_fd, update):
 		pass
 	count = 0
 	while True:
-		update('{0:n} lines read'.format(count))
+		update(f'{count:n} lines read')
 		data = os.read(status_fd, 8)
 		if not data:
 			break
@@ -122,7 +122,7 @@ def char2int(name, empty_value, specials="empty"):
 	char = options.get(name)
 	if not char:
 		return empty_value
-	msg = "%s must be a single iso-8859-1 character (or %s)" % (name, specials,)
+	msg = f"{name} must be a single iso-8859-1 character (or {specials})"
 	if isinstance(char, bytes):
 		char = uni(char)
 	try:
@@ -226,7 +226,7 @@ def prepare(job, slices):
 	if options.strip_labels:
 		labels = [x.strip() for x in labels]
 	labels = [options.rename.get(x, x) for x in labels]
-	assert len(labels) == len(set(labels)), "Duplicate labels: %r" % (labels,)
+	assert len(labels) == len(set(labels)), f"Duplicate labels: {labels!r}"
 
 	dw = job.datasetwriter(
 		columns={n: 'bytes' for n in labels if n not in options.discard},
diff --git a/accelerator/standard_methods/a_csvimport_zip.py b/accelerator/standard_methods/a_csvimport_zip.py
index 6ab09acd..31cbc9eb 100644
--- a/accelerator/standard_methods/a_csvimport_zip.py
+++ b/accelerator/standard_methods/a_csvimport_zip.py
@@ -120,7 +120,7 @@ def tmpfn():
 				used_names.add(name)
 				res.append((next(tmpfn), info, name, fn,))
 	if namemap:
-		raise Exception("The following files were not found in %s: %r" % (options.filename, set(namemap),))
+		raise Exception(f"The following files were not found in {options.filename}: {set(namemap)!r}")
 	if options.chaining == 'by_filename':
 		res.sort(key=lambda x: x[3])
 	if options.chaining == 'by_dsname':
@@ -169,7 +169,7 @@ def synthesis(prepare_res):
 		for fn, info, dsn in lst:
 			update(msg.step('importing'))
 			opts.filename = fn
-			show_fn = '%s:%s' % (options.filename, info.filename,)
+			show_fn = f'{options.filename}:{info.filename}'
 			ds = build('csvimport', options=opts, previous=previous, caption='Import of ' + show_fn).dataset()
 			previous = ds.link_to_here(dsn, filename=show_fn)
 			if options.chaining == 'off':
diff --git a/accelerator/standard_methods/a_dataset_checksum.py b/accelerator/standard_methods/a_dataset_checksum.py
index 0d7b25c1..2997c995 100644
--- a/accelerator/standard_methods/a_dataset_checksum.py
+++ b/accelerator/standard_methods/a_dataset_checksum.py
@@ -91,7 +91,7 @@ def prepare():
 			translators[n] = sortdicts
 		elif col.type == 'pickle':
 			translators[n] = sortdicts
-			print('WARNING: Column %s is pickle, may not work' % (n,))
+			print(f'WARNING: Column {n} is pickle, may not work')
 		else:
 			translators[n] = bytesrepr
 	return columns, translators
@@ -116,5 +116,5 @@ def synthesis(prepare_res, analysis_res):
 	else:
 		all = chain.from_iterable(analysis_res)
 	res = md5(b''.join(all)).hexdigest()
-	print("%s: %s" % (datasets.source, res,))
+	print(f"{datasets.source}: {res}")
 	return DotDict(sum=int(res, 16), sort=options.sort, columns=prepare_res[0], source=datasets.source)
diff --git a/accelerator/standard_methods/a_dataset_checksum_chain.py b/accelerator/standard_methods/a_dataset_checksum_chain.py
index 6341adbd..07473191 100644
--- a/accelerator/standard_methods/a_dataset_checksum_chain.py
+++ b/accelerator/standard_methods/a_dataset_checksum_chain.py
@@ -44,5 +44,5 @@ def synthesis():
 	for src in jobs:
 		data = build('dataset_checksum', columns=options.columns, sort=options.sort, source=src).load()
 		sum ^= data.sum
-	print("Total: %016x" % (sum,))
+	print(f"Total: {sum:016x}")
 	return DotDict(sum=sum, columns=data.columns, sort=options.sort, sources=jobs)
diff --git a/accelerator/standard_methods/a_dataset_concat.py b/accelerator/standard_methods/a_dataset_concat.py
index e378b661..111b688a 100644
--- a/accelerator/standard_methods/a_dataset_concat.py
+++ b/accelerator/standard_methods/a_dataset_concat.py
@@ -35,9 +35,9 @@ def prepare(job):
 	hashlabel = datasets.source.hashlabel
 	for ds in chain:
 		if columns != {name: col.type for name, col in ds.columns.items()}:
-			raise Exception('Dataset %s does not have the same columns as %s' % (ds.quoted, datasets.source.quoted,))
+			raise Exception(f'Dataset {ds.quoted} does not have the same columns as {datasets.source.quoted}')
 		if hashlabel != ds.hashlabel:
-			raise Exception('Dataset %s has hashlabel %r, expected %r' % (ds.quoted, ds.hashlabel, hashlabel,))
+			raise Exception(f'Dataset {ds.quoted} has hashlabel {ds.hashlabel!r}, expected {hashlabel!r}')
 	dw = job.datasetwriter(hashlabel=hashlabel, previous=datasets.previous, copy_mode=True)
 	for name, t in sorted(columns.items()):
 		dw.add(name, t, none_support=chain.none_support(name))
diff --git a/accelerator/standard_methods/a_dataset_fanout.py b/accelerator/standard_methods/a_dataset_fanout.py
index 464f5b2f..97f83246 100644
--- a/accelerator/standard_methods/a_dataset_fanout.py
+++ b/accelerator/standard_methods/a_dataset_fanout.py
@@ -52,7 +52,7 @@ def prepare(job):
 	seen_all = set(chain[0].columns)
 	for ds in chain:
 		if options.column not in ds.columns:
-			raise Exception('%r does not have column %r' % (ds, options.column,))
+			raise Exception(f'{ds!r} does not have column {options.column!r}')
 		hashlabel.add(ds.hashlabel)
 		seen_all &= set(ds.columns)
 		for name, col in ds.columns.items():
@@ -60,7 +60,7 @@ def prepare(job):
 			none_support[name] |= col.none_support
 	seen_all.discard(options.column)
 	if not seen_all:
-		raise Exception('Chain has no common columns (except %r)' % (options.column,))
+		raise Exception(f'Chain has no common columns (except {options.column!r})')
 	columns = {k: columns[k] for k in seen_all}
 	if len(hashlabel) == 1:
 		hashlabel = hashlabel.pop()
@@ -86,7 +86,7 @@ def prepare(job):
 		if len(types) > 1 and not (types - {'int32', 'int64', 'float32', 'float64'}):
 			types = {'number'}
 		if len(types) > 1:
-			raise Exception("Column %r has incompatible types: %r" % (name, types,))
+			raise Exception(f"Column {name!r} has incompatible types: {types!r}")
 		columns[name] = (types.pop(), none_support[name],)
 
 	collect = subjobs.build(
@@ -103,7 +103,7 @@ def prepare(job):
 	else:
 		previous = {}
 
-	with status('Creating %d datasets' % (len(values),)):
+	with status(f'Creating {len(values)} datasets'):
 		writers = {
 			name: job.datasetwriter(
 				name=name,
diff --git a/accelerator/standard_methods/a_dataset_type.py b/accelerator/standard_methods/a_dataset_type.py
index a3f310e6..bb381252 100644
--- a/accelerator/standard_methods/a_dataset_type.py
+++ b/accelerator/standard_methods/a_dataset_type.py
@@ -131,7 +131,7 @@ def prepare_one(ix, source, chain, job, slices, previous_res):
 	for k, v in options.rename.items():
 		if k in source.columns:
 			if v in rev_rename:
-				raise Exception('Both column %r and column %r rename to %r (in %s)' % (rev_rename[v], k, v, source_name))
+				raise Exception(f'Both column {rev_rename[v]!r} and column {k!r} rename to {v!r} (in {source_name})')
 			if v is not None:
 				rev_rename[v] = k
 			if v in column2type:
@@ -153,10 +153,10 @@ def prepare_one(ix, source, chain, job, slices, previous_res):
 	none_support = set()
 	for colname, coltype in column2type.items():
 		if colname not in source.columns:
-			raise Exception("Dataset %s doesn't have a column named %r (has %r)" % (source_name, colname, set(source.columns),))
+			raise Exception(f"Dataset {source_name} doesn't have a column named {colname!r} (has {set(source.columns)!r})")
 		dc = source.columns[colname]
 		if dc.type not in byteslike_types:
-			raise Exception("Dataset %s column %r is type %s, must be one of %r" % (source_name, colname, dc.type, byteslike_types,))
+			raise Exception(f"Dataset {source_name} column {colname!r} is type {dc.type}, must be one of {byteslike_types!r}")
 		coltype = coltype.split(':', 1)[0]
 		if coltype.endswith('+None'):
 			coltype = coltype[:-5]
@@ -187,7 +187,7 @@ def prepare_one(ix, source, chain, job, slices, previous_res):
 		parent = source
 	if hashlabel and hashlabel not in columns:
 		if options.hashlabel:
-			raise Exception("Can't rehash %s on discarded column %r." % (source_name, hashlabel,))
+			raise Exception(f"Can't rehash {source_name} on discarded column {hashlabel!r}.")
 		hashlabel = None # it gets inherited from the parent if we're keeping it.
 		hashlabel_override = False
 	columns = {
@@ -227,7 +227,7 @@ def prepare_one(ix, source, chain, job, slices, previous_res):
 		dw = job.datasetwriter(
 			name=ds_name,
 			columns=columns,
-			caption='%s (from %s)' % (options.caption, source_name,),
+			caption=f'{options.caption} (from {source_name})',
 			hashlabel=hashlabel,
 			hashlabel_override=hashlabel_override,
 			filename=filename,
@@ -464,9 +464,9 @@ def one_column(vars, colname, coltype, out_fns, for_hasher=False):
 	offsets = []
 	max_counts = []
 	d = vars.source
-	assert colname in d.columns, '%s not in %s' % (colname, d.quoted,)
+	assert colname in d.columns, f'{colname} not in {d.quoted}'
 	if not is_null_converter:
-		assert d.columns[colname].type in byteslike_types, '%s has bad type in %s' % (colname, d.quoted,)
+		assert d.columns[colname].type in byteslike_types, f'{colname} has bad type in {d.quoted}'
 	in_fns.append(d.column_filename(colname, vars.sliceno))
 	in_msgnames.append('%s column %s slice %d' % (d.quoted, quote(colname), vars.sliceno,))
 	if d.columns[colname].offsets:
@@ -520,7 +520,7 @@ def one_column(vars, colname, coltype, out_fns, for_hasher=False):
 	else:
 		# python func
 		if for_hasher:
-			raise Exception("Can't hash %s on column of type %s." % (vars.source_name, coltype,))
+			raise Exception(f"Can't hash {vars.source_name} on column of type {coltype}.")
 		nodefault = object()
 		if colname in options.defaults:
 			default_value = options.defaults[colname]
@@ -576,7 +576,7 @@ def one_column(vars, colname, coltype, out_fns, for_hasher=False):
 					badmap[ix // 8] = bv | (1 << (ix % 8))
 					continue
 				else:
-					raise Exception("Invalid value %r with no default in %r in %s" % (v, colname, vars.source_name,))
+					raise Exception(f"Invalid value {v!r} with no default in {colname!r} in {vars.source_name}")
 			if do_minmax and v is not None:
 				if col_min is None:
 					col_min = col_max = v
@@ -611,8 +611,8 @@ def print(msg=''):
 				ds_name = dw.quoted_ds_name
 			else:
 				ds_name = quote(dws[0].ds_name[:-1] + '')
-			header = '%s -> %s' % (source_name, ds_name)
-			builtins.print('%s\n%s' % (header, '=' * len(header)))
+			header = f'{source_name} -> {ds_name}'
+			builtins.print(f"{header}\n{'=' * len(header)}")
 			header_printed[0] = True
 		builtins.print(msg)
 	lines = source.lines
@@ -636,7 +636,7 @@ def print(msg=''):
 		for colname in sorted(options.defaults):
 			defaulted = [data[2].get(colname, 0) for data in analysis_res]
 			if sum(defaulted):
-				print('    %s:' % (colname,))
+				print(f'    {colname}:')
 				print('        Slice   Defaulted line count')
 				slicecnt = 0
 				for sliceno, cnt in enumerate(defaulted):
diff --git a/accelerator/standard_methods/a_dataset_unroundrobin.py b/accelerator/standard_methods/a_dataset_unroundrobin.py
index f04a3565..2b569e6c 100644
--- a/accelerator/standard_methods/a_dataset_unroundrobin.py
+++ b/accelerator/standard_methods/a_dataset_unroundrobin.py
@@ -47,7 +47,7 @@ def prepare(job):
 		copy_mode=True,
 	)
 	if options.trigger_column:
-		assert options.trigger_column in datasets.source.columns, "Trigger column %r not in %s" % (options.trigger_column, datasets.source,)
+		assert options.trigger_column in datasets.source.columns, f"Trigger column {options.trigger_column!r} not in {datasets.source}"
 		ix = sorted(datasets.source.columns).index(options.trigger_column)
 	else:
 		ix = -1
diff --git a/accelerator/standard_methods/c_backend_support.py b/accelerator/standard_methods/c_backend_support.py
index ecc6da59..b7df0f94 100644
--- a/accelerator/standard_methods/c_backend_support.py
+++ b/accelerator/standard_methods/c_backend_support.py
@@ -111,7 +111,7 @@ def make_source(name, functions, protos, extra_functions, extra_method_defs, wra
 	method_defs.extend(extra_method_defs)
 	code.append(_init_code_template % dict(methods=',\n\t'.join(method_defs), name=name,))
 	hash = hashlib.sha1(b''.join(c.encode('ascii') for c in code)).hexdigest()
-	code.insert(-1, 'static char source_hash[] = "%s";\n' % (hash,))
+	code.insert(-1, f'static char source_hash[] = "{hash}";\n')
 	code = ''.join(code)
 	return code, hash
 
@@ -127,7 +127,7 @@ def str2c(s):
 				s = s.encode('utf-8')
 			return s
 	else:
-		print('[%s] Backend modified since module was compiled, falling back to cffi for development.' % (name,), file=sys.stderr)
+		print(f'[{name}] Backend modified since module was compiled, falling back to cffi for development.', file=sys.stderr)
 		import cffi
 		ffi = cffi.FFI()
 
diff --git a/accelerator/standard_methods/dataset_type.py b/accelerator/standard_methods/dataset_type.py
index f04e44e1..557dee02 100644
--- a/accelerator/standard_methods/dataset_type.py
+++ b/accelerator/standard_methods/dataset_type.py
@@ -650,8 +650,8 @@ def _test():
 	known = set(v for v in _convfuncs if ':' not in v)
 	copy_missing = known - set(copy_types)
 	copy_extra = set(copy_types) - known
-	assert not copy_missing, 'copy_types missing %r' % (copy_missing,)
-	assert not copy_extra, 'copy_types contains unexpected %r' % (copy_extra,)
+	assert not copy_missing, f'copy_types missing {copy_missing!r}'
+	assert not copy_extra, f'copy_types contains unexpected {copy_extra!r}'
 
 
 convert_template = r'''
diff --git a/accelerator/statmsg.py b/accelerator/statmsg.py
index 60098331..6e376ec3 100644
--- a/accelerator/statmsg.py
+++ b/accelerator/statmsg.py
@@ -128,14 +128,14 @@ def _start(msg, parent_pid, is_analysis=False):
 		analysis_cookie = ''
 	_send('start', '%d\0%s\0%s\0%f' % (parent_pid, analysis_cookie, msg, monotonic(),))
 	def update(msg):
-		_send('update', '%s\0\0%s' % (msg, analysis_cookie,))
+		_send('update', f'{msg}\x00\x00{analysis_cookie}')
 	return update
 
 def _end(pid=None):
 	_send('end', '', pid=pid)
 
 def _output(pid, msg):
-	_send('output', '%f\0%s' % (monotonic(), msg,), pid=pid)
+	_send('output', f'{monotonic():f}\x00{msg}', pid=pid)
 
 def _clear_output(pid):
 	_send('output', '', pid=pid)
@@ -162,7 +162,7 @@ def fmt(tree, start_indent=0):
 			current = last[0].summary
 			if len(last[0].stack) > 1 and not current[1].endswith('analysis'):
 				msg, t, _ = last[0].stack[1]
-				current = (current[0], '%s %s' % (current[1], msg,), t,)
+				current = (current[0], f'{current[1]} {msg}', t,)
 	except Exception:
 		print_exc(file=sys.stderr)
 		res.append((0, 0, 'ERROR', monotonic()))
@@ -255,9 +255,9 @@ def statmsg_sink(sock):
 						del d
 					status_tree.pop(pid, None)
 				else:
-					print('UNKNOWN MESSAGE: %r' % (data,))
+					print(f'UNKNOWN MESSAGE: {data!r}')
 		except Exception:
-			print('Failed to process %r:' % (data,), file=sys.stderr)
+			print(f'Failed to process {data!r}:', file=sys.stderr)
 			print_exc(file=sys.stderr)
 
 
diff --git a/accelerator/subjobs.py b/accelerator/subjobs.py
index 5039815e..fc3dbad0 100644
--- a/accelerator/subjobs.py
+++ b/accelerator/subjobs.py
@@ -44,14 +44,14 @@ def build(method, options={}, datasets={}, jobs={}, name=None, caption=None, **k
 		_bad_kws = set(getarglist(_a.call_method))
 	bad_kws = _bad_kws & set(kw)
 	if bad_kws:
-		raise Exception('subjobs.build does not accept these keywords: %r' % (bad_kws,))
+		raise Exception(f'subjobs.build does not accept these keywords: {bad_kws!r}')
 	def run():
 		return _a.call_method(method, options=options, datasets=datasets, jobs=jobs, record_as=name, caption=caption, **kw)
 	try:
 		if name or caption:
-			msg = 'Building subjob %s' % (name or method,)
+			msg = f'Building subjob {name or method}'
 			if caption:
-				msg += ' "%s"' % (caption,)
+				msg += f' "{caption}"'
 			with status(msg):
 				jid = run()
 		else:
diff --git a/accelerator/test_methods/a_test_board_metadata.py b/accelerator/test_methods/a_test_board_metadata.py
index e0a4f88e..ce1e664c 100644
--- a/accelerator/test_methods/a_test_board_metadata.py
+++ b/accelerator/test_methods/a_test_board_metadata.py
@@ -119,14 +119,14 @@ def crc(data):
 			fh.write(contents)
 		modified_contents = get(filename)
 		if contents == modified_contents:
-			raise Exception('%s was not modified by board' % (filename,))
+			raise Exception(f'{filename} was not modified by board')
 		filename = 'modified.' + filename
 		with open(filename, 'wb') as fh:
 			fh.write(modified_contents)
 		if not any(modified_contents.startswith(v) for v in (want_head if isinstance(want_head, set) else (want_head,))):
-			raise Exception('Expected %s to start with %r, but it did not' % (filename, want_head,))
+			raise Exception(f'Expected {filename} to start with {want_head!r}, but it did not')
 		if not any(modified_contents.endswith(v) for v in (want_tail if isinstance(want_tail, set) else (want_tail,))):
-			raise Exception('Expected %s to end with %r, but it did not' % (filename, want_tail,))
+			raise Exception(f'Expected {filename} to end with {want_tail!r}, but it did not')
 		got = check_output(options.command_prefix + ['sherlock', filename])
 		got = got.decode('utf-8').strip()
 		if has_extra_block:
@@ -134,7 +134,7 @@ def crc(data):
 		else:
 			want_jobs = job
 		if got != want_jobs:
-			raise Exception('Expected "ax sherlock %s" to give %r, got %r' % (filename, want_jobs, got,))
+			raise Exception(f'Expected "ax sherlock {filename}" to give {want_jobs!r}, got {got!r}')
 
 	p.terminate()
 	p.wait()
diff --git a/accelerator/test_methods/a_test_csvexport_all_coltypes.py b/accelerator/test_methods/a_test_csvexport_all_coltypes.py
index ba7bdc82..b1a90a95 100644
--- a/accelerator/test_methods/a_test_csvexport_all_coltypes.py
+++ b/accelerator/test_methods/a_test_csvexport_all_coltypes.py
@@ -47,7 +47,7 @@ def synthesis(job):
 		'unicode',
 	}
 	check = {n for n in _convfuncs if not n.startswith('parsed:')}
-	assert todo == check, 'Missing/extra column types: %r %r' % (check - todo, todo - check,)
+	assert todo == check, f'Missing/extra column types: {check - todo!r} {todo - check!r}'
 	for name in sorted(todo):
 		t = name
 		dw.add(name, t, none_support=True)
@@ -122,13 +122,13 @@ def synthesis(job):
 			'None', 'never', 'None',
 		)),
 	):
-		with status("Checking with sep=%r, q=%r, none_as=%r" % (sep, q, none_as,)):
+		with status(f"Checking with sep={sep!r}, q={q!r}, none_as={none_as!r}"):
 			exp = subjobs.build('csvexport', filename='test.csv', separator=sep, source=ds, quote_fields=q, none_as=none_as, lazy_quotes=False)
 			with exp.open('test.csv', 'r', encoding='utf-8') as fh:
 				def expect(*a):
 					want = sep.join(q + v.replace(q, q + q) + q for v in a) + '\n'
 					got = next(fh)
-					assert want == got, 'wanted %r, got %r from %s (export of %s)' % (want, got, exp, ds,)
+					assert want == got, f'wanted {want!r}, got {got!r} from {exp} (export of {ds})'
 				expect(*sorted(todo))
 				expect(
 					'a', 'True', 'hello',
diff --git a/accelerator/test_methods/a_test_csvexport_chains.py b/accelerator/test_methods/a_test_csvexport_chains.py
index 9daed14d..981062df 100644
--- a/accelerator/test_methods/a_test_csvexport_chains.py
+++ b/accelerator/test_methods/a_test_csvexport_chains.py
@@ -28,7 +28,7 @@ def verify(want, **kw):
 	job = subjobs.build('csvexport', labelsonfirstline=False, **kw)
 	with job.open('result.csv') as fh:
 		got = fh.read()
-	assert want == got, 'wanted %r, got %r' % (want, got,)
+	assert want == got, f'wanted {want!r}, got {got!r}'
 	return job
 
 def synthesis(job):
diff --git a/accelerator/test_methods/a_test_csvexport_naming.py b/accelerator/test_methods/a_test_csvexport_naming.py
index 9e11bf65..238f54c3 100644
--- a/accelerator/test_methods/a_test_csvexport_naming.py
+++ b/accelerator/test_methods/a_test_csvexport_naming.py
@@ -51,4 +51,4 @@ def synthesis(job):
 			want = b'a\n1\n'
 		else:
 			want = b'a\n0\n1\n2\n'
-		assert want == got, 'wanted %r, got %r in %s' % (want, got, fn)
+		assert want == got, f'wanted {want!r}, got {got!r} in {fn}'
diff --git a/accelerator/test_methods/a_test_csvexport_quoting.py b/accelerator/test_methods/a_test_csvexport_quoting.py
index 7fd550c8..22ba2e3a 100644
--- a/accelerator/test_methods/a_test_csvexport_quoting.py
+++ b/accelerator/test_methods/a_test_csvexport_quoting.py
@@ -82,13 +82,13 @@ def verify(source, lazy_quotes, q, sep, expect, **kw):
 		quote_func = lambda v: q + v.replace(q, q + q) + q
 	want = '\n'.join(sep.join(map(quote_func, line)) for line in expect)
 	if want != got:
-		print('Unhappy with %s:' % (j.filename('result.csv'),))
+		print(f"Unhappy with {j.filename('result.csv')}:")
 		print()
 		print('Expected:')
 		print(want)
 		print('Got:')
 		print(got)
-		raise Exception('csvexport failed with quote_fields=%r, separator=%r, lazy_quotes=%r' % (q, sep, lazy_quotes,))
+		raise Exception(f'csvexport failed with quote_fields={q!r}, separator={sep!r}, lazy_quotes={lazy_quotes!r}')
 
 def make_lazy(sep, q):
 	if q == '"':
diff --git a/accelerator/test_methods/a_test_csvexport_separators.py b/accelerator/test_methods/a_test_csvexport_separators.py
index 51eb7bb1..271582b9 100644
--- a/accelerator/test_methods/a_test_csvexport_separators.py
+++ b/accelerator/test_methods/a_test_csvexport_separators.py
@@ -45,7 +45,7 @@ def verify(data, filename):
 			open_func = open
 		with open_func(j.filename(filename), 'rb') as fh:
 			got = fh.read()
-		assert want == got, "Expected %s/%s to contain %r, but contained %r" % (j, filename, want, got,)
+		assert want == got, f"Expected {j}/{filename} to contain {want!r}, but contained {got!r}"
 	for separator in ('', '\0', 'wheeee'):
 		for line_separator in ('', '\0', 'woooooo'):
 			for quote in ('', 'qqq'):
diff --git a/accelerator/test_methods/a_test_csvimport_corner_cases.py b/accelerator/test_methods/a_test_csvimport_corner_cases.py
index 05ffa371..ff05c0a9 100644
--- a/accelerator/test_methods/a_test_csvimport_corner_cases.py
+++ b/accelerator/test_methods/a_test_csvimport_corner_cases.py
@@ -70,10 +70,10 @@ def verify_ds(options, d, d_bad, d_skipped, filename, d_columns=None):
 		except ValueError:
 			# We have a few non-numeric ones
 			pass
-		assert ix in d, "Bad index %r in %r (%s)" % (ix, filename, jid,)
-		assert a == b == d[ix], "Wrong data for line %r in %r (%s)" % (ix, filename, jid,)
+		assert ix in d, f"Bad index {ix!r} in {filename!r} ({jid})"
+		assert a == b == d[ix], f"Wrong data for line {ix!r} in {filename!r} ({jid})"
 		del d[ix]
-	assert not d, "Not all lines returned from %r (%s), %r missing" % (filename, jid, set(d.keys()),)
+	assert not d, f"Not all lines returned from {filename!r} ({jid}), {set(d.keys())!r} missing"
 	if options.get("allow_bad"):
 		bad_ds = Dataset(jid, "bad")
 		for ix, data in bad_ds.iterate(None, ["lineno", "data"]):
@@ -81,7 +81,7 @@ def verify_ds(options, d, d_bad, d_skipped, filename, d_columns=None):
 			assert data == d_bad[ix], "Wrong saved bad line %d in %r (%s/bad).\nWanted %r.\nGot    %r." % (ix, filename, jid, d_bad[ix], data,)
 			del d_bad[ix]
 		verify_minmax(bad_ds, "lineno")
-	assert not d_bad, "Not all bad lines returned from %r (%s), %r missing" % (filename, jid, set(d_bad.keys()),)
+	assert not d_bad, f"Not all bad lines returned from {filename!r} ({jid}), {set(d_bad.keys())!r} missing"
 
 	if options.get("comment") or options.get("skip_lines"):
 		skipped_ds = Dataset(jid, "skipped")
@@ -90,11 +90,11 @@ def verify_ds(options, d, d_bad, d_skipped, filename, d_columns=None):
 			assert data == d_skipped[ix], "Wrong saved skipped line %d in %r (%s/skipped).\nWanted %r.\nGot    %r." % (ix, filename, jid, d_skipped[ix], data,)
 			del d_skipped[ix]
 		verify_minmax(skipped_ds, "lineno")
-	assert not d_skipped, "Not all bad lines returned from %r (%s), %r missing" % (filename, jid, set(d_skipped.keys()),)
+	assert not d_skipped, f"Not all bad lines returned from {filename!r} ({jid}), {set(d_skipped.keys())!r} missing"
 
 	if options.get("lineno_label"):
 		lineno_got = dict(ds.iterate(None, [d_columns[0], options.get("lineno_label")]))
-		assert lineno_got == lineno_want, "%r != %r" % (lineno_got, lineno_want,)
+		assert lineno_got == lineno_want, f"{lineno_got!r} != {lineno_want!r}"
 		verify_minmax(ds, options["lineno_label"])
 
 def verify_minmax(ds, colname):
@@ -102,14 +102,14 @@ def verify_minmax(ds, colname):
 	minmax_want = (min(data) , max(data),) if data else (None, None,)
 	col = ds.columns[colname]
 	minmax_got = (col.min, col.max,)
-	assert minmax_got == minmax_want, "%s: %r != %r" % (ds, minmax_got, minmax_want,)
+	assert minmax_got == minmax_want, f"{ds}: {minmax_got!r} != {minmax_want!r}"
 
 def require_failure(name, options):
 	try:
 		subjobs.build("csvimport", options=options)
 	except JobError:
 		return
-	raise Exception("File with %s was imported without error." % (name,))
+	raise Exception(f"File with {name} was imported without error.")
 
 def check_bad_file(job, name, data):
 	filename = name + ".txt"
@@ -143,7 +143,7 @@ def write(data):
 		for q in (None, 0, 34, 13, 10, 228):
 			if nl == q:
 				continue
-			filename = "no separator.%r.%r.txt" % (nl, q,)
+			filename = f"no separator.{nl!r}.{q!r}.txt"
 			nl_b = bytechr(nl)
 			q_b = bytechr(q) if q else b''
 			wrote_c = Counter()
@@ -160,9 +160,9 @@ def write(data):
 					labels=["data"],
 				))
 			except JobError:
-				raise Exception("Importing %r failed" % (filename,))
+				raise Exception(f"Importing {filename!r} failed")
 			got_c = Counter(Dataset(jid).iterate(None, "data"))
-			assert got_c == wrote_c, "Importing %r (%s) gave wrong contents" % (filename, jid,)
+			assert got_c == wrote_c, f"Importing {filename!r} ({jid}) gave wrong contents"
 
 def check_good_file(job, name, data, d, d_bad={}, d_skipped={}, d_columns=None, **options):
 	filename = name + ".txt"
diff --git a/accelerator/test_methods/a_test_csvimport_zip.py b/accelerator/test_methods/a_test_csvimport_zip.py
index 67b5aa16..9f80a364 100644
--- a/accelerator/test_methods/a_test_csvimport_zip.py
+++ b/accelerator/test_methods/a_test_csvimport_zip.py
@@ -51,7 +51,7 @@ def verify(zipname, inside_filenames, want_ds, **kw):
 	jid = subjobs.build('csvimport_zip', options=opts)
 	for dsn, want_data in want_ds.items():
 		got_data = list(Dataset(jid, dsn).iterate(None, '0'))
-		assert got_data == want_data, "%s/%s from %s didn't contain %r, instead contained %r" % (jid, dsn, zipname, want_data, got_data)
+		assert got_data == want_data, f"{jid}/{dsn} from {zipname} didn't contain {want_data!r}, instead contained {got_data!r}"
 
 def verify_order(want_order, namemap={}, **kw):
 	opts=dict(
@@ -65,13 +65,13 @@ def verify_order(want_order, namemap={}, **kw):
 	for dsn in want_order:
 		b = b'contents of ' + namemap.get(dsn, dsn).encode('ascii')
 		got_data = list(Dataset(jid, dsn).iterate(None, '0'))
-		assert got_data == [b], "%s/%s from 'many files.zip' didn't contain [%r], instead contained %r" % (jid, dsn, b, got_data)
+		assert got_data == [b], f"{jid}/{dsn} from 'many files.zip' didn't contain [{b!r}], instead contained {got_data!r}"
 	got_order = [ds.name for ds in Dataset(jid, want_order[-1]).chain()]
-	assert want_order == got_order, 'Wanted order %r, got %r in %s' % (want_order, got_order, jid,)
+	assert want_order == got_order, f'Wanted order {want_order!r}, got {got_order!r} in {jid}'
 	if len(want_order) > 1: # chaining is actually on, so a default ds is produced
 		got_order = [ds.name for ds in Dataset(jid).chain()]
 		want_order[-1] = 'default'
-		assert want_order == got_order, 'Wanted order %r, got %r in %s' % (want_order, got_order, jid,)
+		assert want_order == got_order, f'Wanted order {want_order!r}, got {got_order!r} in {jid}'
 
 def synthesis():
 	# Simple case, a single file in the zip.
diff --git a/accelerator/test_methods/a_test_dataset_callbacks.py b/accelerator/test_methods/a_test_dataset_callbacks.py
index 8e5a45cc..eb6821a9 100644
--- a/accelerator/test_methods/a_test_dataset_callbacks.py
+++ b/accelerator/test_methods/a_test_dataset_callbacks.py
@@ -157,7 +157,7 @@ def chk_both_post(ds):
 		if slices == 3 and ds.name == '3':
 			# ('3', 3) never happens, so fake it.
 			current_expect.append(5)
-		assert current_expect == current, '%s %r %r'%(ds,current_expect, current)
+		assert current_expect == current, f'{ds} {current_expect!r} {current!r}'
 	for v in ds4.iterate_chain(None, 'a', pre_callback=chk_both_pre, post_callback=chk_both_post):
 		current.append(v)
 	assert seen_pre == set.union(*(set((n, s) for s in range(slices)) for n in '1234'))
diff --git a/accelerator/test_methods/a_test_dataset_column_names.py b/accelerator/test_methods/a_test_dataset_column_names.py
index 12abe9cd..96dbe488 100644
--- a/accelerator/test_methods/a_test_dataset_column_names.py
+++ b/accelerator/test_methods/a_test_dataset_column_names.py
@@ -72,7 +72,7 @@ def synthesis(prepare_res, slices):
 	child = dw.finish()
 	for colname in in_parent + in_child:
 		data = set(child.iterate(None, colname))
-		assert data == {colname + " 1", colname + " 2"}, "Bad data for %s: %r" % (colname, data)
+		assert data == {colname + " 1", colname + " 2"}, f"Bad data for {colname}: {data!r}"
 
 	def chk_internal(name, **kw):
 		internal = ("writers", "w_l", "cyc", "hsh", "next",)
diff --git a/accelerator/test_methods/a_test_dataset_concat.py b/accelerator/test_methods/a_test_dataset_concat.py
index 4756117b..3dcd53a1 100644
--- a/accelerator/test_methods/a_test_dataset_concat.py
+++ b/accelerator/test_methods/a_test_dataset_concat.py
@@ -123,7 +123,7 @@ def chk(source, previous, want_in_chain, want, do_sort=True, none_support=()):
 	def want_fail(why, **kw):
 		try:
 			subjobs.build('dataset_concat', **kw)
-			raise Exception('dataset_concat(%r) should have failed: %s' % (kw, why,))
+			raise Exception(f'dataset_concat({kw!r}) should have failed: {why}')
 		except JobError:
 			pass
 
diff --git a/accelerator/test_methods/a_test_dataset_empty_colname.py b/accelerator/test_methods/a_test_dataset_empty_colname.py
index dcce6a0e..234d7579 100644
--- a/accelerator/test_methods/a_test_dataset_empty_colname.py
+++ b/accelerator/test_methods/a_test_dataset_empty_colname.py
@@ -52,7 +52,7 @@ def chk_order(names, want):
 		ds = dw.finish()
 		for col in want:
 			# '' hashes to 0, so if the hashlabel worked both are in slice 0.
-			assert list(ds.iterate(0, col)) == [col, col], '%r bad in %s' % (col, ds,)
+			assert list(ds.iterate(0, col)) == [col, col], f'{col!r} bad in {ds}'
 		return ds
 	chk_order(['@', '_', ''], {'@': '_', '_': '__', '': '___'})
 	chk_order(['@', '', '_'], {'@': '_', '': '__', '_': '___'})
@@ -68,7 +68,7 @@ def chk_mismatch(ds, good, bad):
 		except DatasetUsageError:
 			pass
 		else:
-			raise Exception('%s accepted hashlabel %r' % (ds, bad,))
+			raise Exception(f'{ds} accepted hashlabel {bad!r}')
 	chk_mismatch(ds, '', '@')
 	dw = job.datasetwriter(name='hl_', hashlabel='_')
 	dw.add('_', 'int32')
diff --git a/accelerator/test_methods/a_test_dataset_fanout.py b/accelerator/test_methods/a_test_dataset_fanout.py
index b60f9d1a..3b21b9f9 100644
--- a/accelerator/test_methods/a_test_dataset_fanout.py
+++ b/accelerator/test_methods/a_test_dataset_fanout.py
@@ -37,19 +37,19 @@ def mk(name, types, lines, hashlabel=None, previous=None):
 	def chk(job, colnames, types, ds2lines, previous={}, hashlabel=None):
 		have_ds = set(ds.name for ds in job.datasets)
 		want_ds = set(ds2lines)
-		assert have_ds == want_ds, 'Job %r should have had datasets %r but had %r' % (job, want_ds, have_ds,)
+		assert have_ds == want_ds, f'Job {job!r} should have had datasets {want_ds!r} but had {have_ds!r}'
 		colnames = sorted(colnames)
 		for ds, lines in ds2lines.items():
 			ds = job.dataset(ds)
-			assert ds.hashlabel == hashlabel, 'Dataset %s should have had hashlabel %s but had %s' % (ds.quoted, hashlabel, ds.hashlabel,)
-			assert ds.previous == previous.get(ds.name), 'Dataset %s should have had previous %s but had %s' % (ds.quoted, previous.get(ds.name), ds.previous,)
+			assert ds.hashlabel == hashlabel, f'Dataset {ds.quoted} should have had hashlabel {hashlabel} but had {ds.hashlabel}'
+			assert ds.previous == previous.get(ds.name), f'Dataset {ds.quoted} should have had previous {previous.get(ds.name)} but had {ds.previous}'
 			ds_colnames = sorted(ds.columns)
-			assert ds_colnames == colnames, 'Dataset %s should have had columns %r but had %r' % (ds.quoted, colnames, ds_colnames,)
+			assert ds_colnames == colnames, f'Dataset {ds.quoted} should have had columns {colnames!r} but had {ds_colnames!r}'
 			ds_types = tuple(col.type for _, col in sorted(ds.columns.items()))
-			assert ds_types == types, 'Dataset %s should have had columns with types %r but had %r' % (ds.quoted, types, ds_types,)
+			assert ds_types == types, f'Dataset {ds.quoted} should have had columns with types {types!r} but had {ds_types!r}'
 			have_lines = sorted(ds.iterate(None))
 			want_lines = sorted(lines)
-			assert have_lines == want_lines, 'Dataset %s should have contained %r but contained %r' % (ds.quoted, want_lines, have_lines,)
+			assert have_lines == want_lines, f'Dataset {ds.quoted} should have contained {want_lines!r} but contained {have_lines!r}'
 
 	# just a simple splitting
 	a = mk('a', ('unicode', 'ascii', 'int64'), [('a', 'a', 1), ('b', 'b', 2), ('a', 'c', 3)], hashlabel='A')
diff --git a/accelerator/test_methods/a_test_dataset_filter_columns.py b/accelerator/test_methods/a_test_dataset_filter_columns.py
index 7c019e76..1a1bba17 100644
--- a/accelerator/test_methods/a_test_dataset_filter_columns.py
+++ b/accelerator/test_methods/a_test_dataset_filter_columns.py
@@ -37,10 +37,10 @@ def chk(j, *want):
 		ds = j.dataset()
 		want = set(want)
 		got = set(ds.columns)
-		assert got == want, "%s should have had columns %r but had %r" % (ds, want, got,)
+		assert got == want, f"{ds} should have had columns {want!r} but had {got!r}"
 		want = list(zip(*[(ord(c) - 96, ord(c)) for c in sorted(want)]))
 		got = list(ds.iterate(None))
-		assert got == want, "%s should have had %r but had %r" % (ds, want, got,)
+		assert got == want, f"{ds} should have had {want!r} but had {got!r}"
 	chk(job, 'a', 'b', 'c', 'd')
 	j = subjobs.build('dataset_filter_columns', source=ds, keep_columns=['a'])
 	chk(j, 'a')
diff --git a/accelerator/test_methods/a_test_dataset_merge.py b/accelerator/test_methods/a_test_dataset_merge.py
index 9ce4468f..6f7e99c6 100644
--- a/accelerator/test_methods/a_test_dataset_merge.py
+++ b/accelerator/test_methods/a_test_dataset_merge.py
@@ -45,7 +45,7 @@ def fail_merge(a, b, **kw):
 		a.merge(b, name='failme', **kw)
 	except DatasetUsageError:
 		return
-	raise Exception("Merging %s and %s with %r didn't fail as it should have" % (a, b, kw,))
+	raise Exception(f"Merging {a} and {b} with {kw!r} didn't fail as it should have")
 
 checks = {}
 def check(ds, want):
@@ -53,7 +53,7 @@ def check(ds, want):
 		checks[ds.name] = want
 	got = list(ds.iterate_chain(None))
 	got.sort()
-	assert got == want, "%s contained %r not %r as expetected" % (ds, got, want,)
+	assert got == want, f"{ds} contained {got!r} not {want!r} as expetected"
 
 def synthesis(params):
 	a0 = mkds('a0', ['0', '1'], [(1, 2), (3, 4), (5, 6)])
@@ -143,4 +143,4 @@ def synthesis(params):
 			subjobs.build('dataset_merge', datasets=dict(source=parents), options=kw)
 		except JobError:
 			continue
-		raise Exception("dataset_merge incorrectly allowed %r with %r" % (parents, kw))
+		raise Exception(f"dataset_merge incorrectly allowed {parents!r} with {kw!r}")
diff --git a/accelerator/test_methods/a_test_dataset_nan.py b/accelerator/test_methods/a_test_dataset_nan.py
index 8d4f0cca..10253152 100644
--- a/accelerator/test_methods/a_test_dataset_nan.py
+++ b/accelerator/test_methods/a_test_dataset_nan.py
@@ -59,8 +59,8 @@ def check(dw, want_min, want_max):
 		ds = dw.finish()
 		for colname, want_min, want_max in zip(['float32', 'float64', 'number'], want_min, want_max):
 			col = ds.columns[colname]
-			assert eq(col.min, want_min), "%s.%s should have had min value %s, but had %s" % (ds, colname, want_min, col.min)
-			assert eq(col.max, want_max), "%s.%s should have had max value %s, but had %s" % (ds, colname, want_max, col.max)
+			assert eq(col.min, want_min), f"{ds}.{colname} should have had min value {want_min}, but had {col.min}"
+			assert eq(col.max, want_max), f"{ds}.{colname} should have had max value {want_max}, but had {col.max}"
 	check(a, [nan, nan, nan], [nan, nan, nan])
 	check(b, [nan, 2, nan], [nan, 2, nan])
 	check(c, [0, 1, 1], [inf, 1, 2])
diff --git a/accelerator/test_methods/a_test_dataset_parsing_writer.py b/accelerator/test_methods/a_test_dataset_parsing_writer.py
index eb349d31..d50be8ad 100644
--- a/accelerator/test_methods/a_test_dataset_parsing_writer.py
+++ b/accelerator/test_methods/a_test_dataset_parsing_writer.py
@@ -49,11 +49,11 @@ def test(typ, write_values, want_values, bad_values=[]):
 			try:
 				write(value)
 			except Exception as e:
-				raise Exception('Failed to write %r to %s column: %r' % (value, typ, e))
+				raise Exception(f'Failed to write {value!r} to {typ} column: {e!r}')
 		for value in ['foo', '1 two'] + bad_values:
 			try:
 				write(value)
-				raise Exception('writer for parsed:%s allowed %r' % (typ, value,))
+				raise Exception(f'writer for parsed:{typ} allowed {value!r}')
 			except (ValueError, OverflowError):
 				pass
 		ds = dw.finish()
diff --git a/accelerator/test_methods/a_test_dataset_rename_columns.py b/accelerator/test_methods/a_test_dataset_rename_columns.py
index 0ae39233..cd544af1 100644
--- a/accelerator/test_methods/a_test_dataset_rename_columns.py
+++ b/accelerator/test_methods/a_test_dataset_rename_columns.py
@@ -53,9 +53,9 @@ def chk_inner(got_ds, want_hashlabel, want_previous, want_coltypes):
 		got_cols = set(got_ds.columns)
 		want_cols = set(want_coltypes)
 		extra = got_cols - want_cols
-		assert not extra, 'got extra columns %r' % (extra,)
+		assert not extra, f'got extra columns {extra!r}'
 		missing = want_cols - got_cols
-		assert not missing, 'missing columns %r' % (missing,)
+		assert not missing, f'missing columns {missing!r}'
 		for colname, want_type in want_coltypes.items():
 			assert got_ds.columns[colname].type == want_type
 			assert list(got_ds.iterate(None, colname)) == [type2value[want_type]]
diff --git a/accelerator/test_methods/a_test_dataset_slice.py b/accelerator/test_methods/a_test_dataset_slice.py
index 62aaeb96..f2f4b7ea 100644
--- a/accelerator/test_methods/a_test_dataset_slice.py
+++ b/accelerator/test_methods/a_test_dataset_slice.py
@@ -68,7 +68,7 @@ def get_chain(sliceno, slice, columns='a'):
 	def assert_fails(sliceno, slice, func=get, columns='a'):
 		try:
 			func(sliceno, slice, columns)
-			raise Exception("Iterating with slice %r should have failed" % (slice,))
+			raise Exception(f"Iterating with slice {slice!r} should have failed")
 		except DatasetError:
 			pass
 	assert_fails(None, -101)
diff --git a/accelerator/test_methods/a_test_dataset_type_None.py b/accelerator/test_methods/a_test_dataset_type_None.py
index 2227adb1..460e37c6 100644
--- a/accelerator/test_methods/a_test_dataset_type_None.py
+++ b/accelerator/test_methods/a_test_dataset_type_None.py
@@ -104,4 +104,4 @@ def synthesis(job):
 				if ds_with_None:
 					want.insert(0, None)
 				got = list(typed.iterate(0, name))
-				assert want == got, 'Column %r in %s has %r, should have %r' % (name, typed.quoted, got, want,)
+				assert want == got, f'Column {name!r} in {typed.quoted} has {got!r}, should have {want!r}'
diff --git a/accelerator/test_methods/a_test_dataset_type_chaining.py b/accelerator/test_methods/a_test_dataset_type_chaining.py
index 9aec167a..03ac05ee 100644
--- a/accelerator/test_methods/a_test_dataset_type_chaining.py
+++ b/accelerator/test_methods/a_test_dataset_type_chaining.py
@@ -41,7 +41,7 @@ def verify_sorted(a, b):
 			b_data = list(map(str, Dataset.iterate_list(None, col, b)))
 			a_data.sort()
 			b_data.sort()
-			assert a_data == b_data, '%r has different contents to %r in column %s' % (a, b, col,)
+			assert a_data == b_data, f'{a!r} has different contents to {b!r} in column {col}'
 	def write(name, previous, low, high, filter=lambda ix: True):
 		dw = job.datasetwriter(
 			name=name,
diff --git a/accelerator/test_methods/a_test_dataset_type_corner_cases.py b/accelerator/test_methods/a_test_dataset_type_corner_cases.py
index 65a66320..eb8258f1 100644
--- a/accelerator/test_methods/a_test_dataset_type_corner_cases.py
+++ b/accelerator/test_methods/a_test_dataset_type_corner_cases.py
@@ -56,7 +56,7 @@ def verify(name, types, bytes_data, want, default=no_default, want_fail=False, a
 		uni_data = [v.decode('ascii') for v in bytes_data]
 		todo += [('ascii', uni_data,), ('unicode', uni_data,)]
 	for coltype, data in todo:
-		dsname = '%s %s' % (name, coltype,)
+		dsname = f'{name} {coltype}'
 		_verify(dsname, types, data, coltype, want, default, want_fail, exact_types, kw)
 
 def _verify(name, types, data, coltype, want, default, want_fail, exact_types, kw):
@@ -71,7 +71,7 @@ def check(got, fromstr, filtered=False):
 			if exact_types:
 				got = [(v, type(v).__name__) for v in got]
 				want1 = [(v, type(v).__name__) for v in want1]
-			assert got == want1, 'Expected %r, got %r from %s.' % (want1, got, fromstr,)
+			assert got == want1, f'Expected {want1!r}, got {got!r} from {fromstr}.'
 	dw = DatasetWriter(name=name, columns={'data': coltype, 'extra': 'bytes'})
 	dw.set_slice(0)
 	for ix, v in enumerate(data):
@@ -89,26 +89,26 @@ def check(got, fromstr, filtered=False):
 		except JobError:
 			if want_fail:
 				continue
-			raise Exception('Typing %r as %s failed.' % (bytes_ds, typ,))
-		assert not want_fail, "Typing %r as %s should have failed, but didn't (%s)." % (bytes_ds, typ, jid)
+			raise Exception(f'Typing {bytes_ds!r} as {typ} failed.')
+		assert not want_fail, f"Typing {bytes_ds!r} as {typ} should have failed, but didn't ({jid})."
 		typed_ds = Dataset(jid)
 		got = list(typed_ds.iterate(0, 'data'))
-		check(got, '%s (typed as %s from %r)' % (typed_ds, typ, bytes_ds,))
+		check(got, f'{typed_ds} (typed as {typ} from {bytes_ds!r})')
 		if opts.get('filter_bad'):
 			bad_ds = Dataset(jid, 'bad')
 			got_bad = list(bad_ds.iterate(0, 'data'))
-			assert got_bad == [b'nah'], "%s should have had a single b'nah', but had %r" % (bad_ds, got_bad,)
+			assert got_bad == [b'nah'], f"{bad_ds} should have had a single b'nah', but had {got_bad!r}"
 		if 'filter_bad' not in opts and not callable(want):
 			opts['filter_bad'] = True
 			opts['column2type']['extra'] = 'int32_10'
 			jid = subjobs.build('dataset_type', datasets=dict(source=bytes_ds), options=opts)
 			typed_ds = Dataset(jid)
 			got = list(typed_ds.iterate(0, 'data'))
-			check(got, '%s (typed as %s from %r with every other line skipped from filter_bad)' % (typed_ds, typ, bytes_ds,), True)
+			check(got, f'{typed_ds} (typed as {typ} from {bytes_ds!r} with every other line skipped from filter_bad)', True)
 			want_bad = [t for t in bytes_ds.iterate(0) if t[1] == b'skip']
 			bad_ds = Dataset(jid, 'bad')
 			got_bad = list(bad_ds.iterate(0))
-			assert got_bad == want_bad, "Expected %r, got %r from %s" % (want_bad, got_bad, bad_ds,)
+			assert got_bad == want_bad, f"Expected {want_bad!r}, got {got_bad!r} from {bad_ds}"
 		used_type(typ)
 
 def test_numbers():
@@ -161,7 +161,7 @@ def test_numbers():
 	verify('floatbool false', ['floatbool'], [b'0', b'-0', b'1', b'1004', b'0.00001', b'inf', b'-1', b' 0 ', b'0.00'], [False, False, True, True, True, True, True, False, False], exact_types=True)
 	verify('floatbool i', ['floatbooli'], [b'1 yes', b'0 no', b'0.00 also no', b'inf yes', b' 0.01y', b''], [True, False, False, True, True, False], exact_types=True)
 	def check_special(got, fromstr):
-		msg = 'Expected [inf, -inf, nan, nan, nan, nan, inf], got %r from %s.' % (got, fromstr,)
+		msg = f'Expected [inf, -inf, nan, nan, nan, nan, inf], got {got!r} from {fromstr}.'
 		for ix, v in ((0, float('inf')), (1, float('-inf')), (-1, float('inf'))):
 			assert got[ix] == v, msg
 		for ix in range(2, 6):
@@ -291,18 +291,18 @@ def good(want, *a):
 		for value in a:
 			tests[pattern].append((value, want))
 			got = strptime(value, pattern)
-			assert got == want, "Parsing %r as %r\n    expected %s\n    got      %s" % (value, pattern, want, got,)
+			assert got == want, f"Parsing {value!r} as {pattern!r}\n    expected {want}\n    got      {got}"
 			value += 'x'
 			got, remaining = strptime_i(value, pattern)
-			assert got == want, "Parsing %r as %r\n    expected %s\n    got      %s" % (value, pattern, want, got,)
-			assert remaining == b'x', "Parsing %r as %r left %r unparsed, expected %r" % (value, pattern, remaining, b'x',)
+			assert got == want, f"Parsing {value!r} as {pattern!r}\n    expected {want}\n    got      {got}"
+			assert remaining == b'x', f"Parsing {value!r} as {pattern!r} left {remaining!r} unparsed, expected {b'x'!r}"
 
 	def bad(*a):
 		for value in a:
 			tests[pattern].append((value, None))
 			try:
 				got = strptime(value, pattern)
-				raise Exception("Parsing %r as %r gave %s, should have failed" % (value, pattern, got,))
+				raise Exception(f"Parsing {value!r} as {pattern!r} gave {got}, should have failed")
 			except ValueError:
 				pass
 
@@ -921,7 +921,7 @@ def check(type_as, fix):
 				for got, wrote, good in zip(got, wrote, good):
 					if good is not None:
 						good = fix(good)
-					assert got == good, 'Typing %r as %r gave %r, expected %r' % (wrote, column2type[col], got, good,)
+					assert got == good, f'Typing {wrote!r} as {column2type[col]!r} gave {got!r}, expected {good!r}'
 
 		check('datetime', lambda dt: dt)
 		check('date', lambda dt: dt.date())
@@ -943,7 +943,7 @@ def check(type_as, fix):
 			('date', date),
 			('datetime', datetime),
 		):
-			verify('nearly good %s YYYY-MM-DD' % (type_as,), ['%s:%s' % (type_as, pattern,)], [b'2019-02-29', b'1970-02-31', b'1980-06-31', b'1992-02-29'], [None, None, None, func(1992, 2, 29)], None, False)
+			verify(f'nearly good {type_as} YYYY-MM-DD', [f'{type_as}:{pattern}'], [b'2019-02-29', b'1970-02-31', b'1980-06-31', b'1992-02-29'], [None, None, None, func(1992, 2, 29)], None, False)
 
 
 def test_filter_bad_across_types():
@@ -1002,10 +1002,10 @@ def add_want(ix):
 		)
 		typed_ds = Dataset(jid)
 		got = list(typed_ds.iterate(0, cols_to_check))
-		assert got == want, "Expected %r, got %r from %s (from %r%s)" % (want, got, typed_ds, source_ds, ' with defaults' if defaults else '')
+		assert got == want, f"Expected {want!r}, got {got!r} from {typed_ds} (from {source_ds!r}{' with defaults' if defaults else ''})"
 		bad_ds = Dataset(jid, 'bad')
 		got_bad = list(bad_ds.iterate(0, sorted(columns)))
-		assert got_bad == want_bad, "Expected %r, got %r from %s (from %r%s)" % (want_bad, got_bad, bad_ds, source_ds, ' with defaults' if defaults else '')
+		assert got_bad == want_bad, f"Expected {want_bad!r}, got {got_bad!r} from {bad_ds} (from {source_ds!r}{' with defaults' if defaults else ''})"
 		# make more lines "ok" for the second lap
 		if not defaults:
 			want_bad.pop(0) # number:int
@@ -1213,7 +1213,7 @@ def test_column_discarding():
 		column2type=dict(a='ascii', c='ascii'),
 		discard_untyped=True,
 	).dataset()
-	assert sorted(ac_implicit.columns) == ['a', 'c'], '%s: %r' % (ac_implicit, sorted(ac_implicit.columns),)
+	assert sorted(ac_implicit.columns) == ['a', 'c'], f'{ac_implicit}: {sorted(ac_implicit.columns)!r}'
 	assert list(ac_implicit.iterate(None)) == [('a', 'c',)], ac_implicit
 
 	# Discard b explicitly
@@ -1223,7 +1223,7 @@ def test_column_discarding():
 		column2type=dict(a='ascii', c='ascii'),
 		rename=dict(b=None),
 	).dataset()
-	assert sorted(ac_explicit.columns) == ['a', 'c'], '%s: %r' % (ac_explicit, sorted(ac_explicit.columns),)
+	assert sorted(ac_explicit.columns) == ['a', 'c'], f'{ac_explicit}: {sorted(ac_explicit.columns)!r}'
 	assert list(ac_explicit.iterate(None)) == [('a', 'c',)], ac_explicit
 
 	# Discard c by overwriting it with b. Keep untyped b.
@@ -1233,7 +1233,7 @@ def test_column_discarding():
 		column2type=dict(a='ascii', c='ascii'),
 		rename=dict(b='c'),
 	).dataset()
-	assert sorted(ac_bASc.columns) == ['a', 'b', 'c'], '%s: %r' % (ac_bASc, sorted(ac_bASc.columns),)
+	assert sorted(ac_bASc.columns) == ['a', 'b', 'c'], f'{ac_bASc}: {sorted(ac_bASc.columns)!r}'
 	assert list(ac_bASc.iterate(None)) == [('a', b'b', 'b',)], ac_bASc
 
 	# Discard c by overwriting it with b. Also type b as a different type.
@@ -1243,7 +1243,7 @@ def test_column_discarding():
 		column2type=dict(a='ascii', b='strbool', c='ascii'),
 		rename=dict(b='c'),
 	).dataset()
-	assert sorted(abc_bASc.columns) == ['a', 'b', 'c'], '%s: %r' % (abc_bASc, sorted(abc_bASc.columns),)
+	assert sorted(abc_bASc.columns) == ['a', 'b', 'c'], f'{abc_bASc}: {sorted(abc_bASc.columns)!r}'
 	assert list(abc_bASc.iterate(None)) == [('a', True, 'b',)], abc_bASc
 
 def test_rehash_with_empty_slices():
diff --git a/accelerator/test_methods/a_test_dataset_type_hashing.py b/accelerator/test_methods/a_test_dataset_type_hashing.py
index 24e98346..4528fb2a 100644
--- a/accelerator/test_methods/a_test_dataset_type_hashing.py
+++ b/accelerator/test_methods/a_test_dataset_type_hashing.py
@@ -79,7 +79,7 @@ def synthesis(job, slices):
 
 	# Test various types for hashing and discarding of bad lines.
 	for hl in (None, 'a', 'b', 'c'):
-		dw = job.datasetwriter(name='hashed on %s' % (hl,), columns={'a': 'unicode', 'b': 'unicode', 'c': 'unicode'}, hashlabel=hl)
+		dw = job.datasetwriter(name=f'hashed on {hl}', columns={'a': 'unicode', 'b': 'unicode', 'c': 'unicode'}, hashlabel=hl)
 		w = dw.get_split_write()
 		for ix in range(1000):
 			w(unicode(ix), '%d.%d' % (ix, ix % 5 == 0), ('{"a": %s}' if ix % 3 else '%d is bad') % (ix,))
@@ -200,12 +200,12 @@ def synthesis(job, slices):
 					key = key.decode('ascii')
 				else:
 					key = unicode(key)
-				assert data.get(key) == line[1:], "%s (hl %s) didn't have the right data for line %r" % (ds, hl, line[0],)
+				assert data.get(key) == line[1:], f"{ds} (hl {hl}) didn't have the right data for line {line[0]!r}"
 				hv = line[sorted(src_ds.columns).index(hl)]
-				assert hl_hash(hv) % slices == sliceno, "%s (hl %s) didn't hash %r correctly" % (ds, hl, hv,)
-				assert key not in seen, "%s (hl %s) repeated line %s" % (ds, hl, line[0],)
+				assert hl_hash(hv) % slices == sliceno, f"{ds} (hl {hl}) didn't hash {hv!r} correctly"
+				assert key not in seen, f"{ds} (hl {hl}) repeated line {line[0]}"
 				seen.add(key)
-		assert seen == {'42', 'None', '18'}, "%s didn't have all lines (%r)" % (ds, seen,)
+		assert seen == {'42', 'None', '18'}, f"{ds} didn't have all lines ({seen!r})"
 
 def test(src_ds, opts, expect_lines):
 	opts = DotDict(opts)
@@ -213,7 +213,7 @@ def rename(colname):
 		return opts.get('rename', {}).get(colname, colname)
 	cols = set(opts.column2type)
 	opts.discard_untyped = True
-	msg = 'Testing with types %s' % (', '.join(v for k, v in sorted(opts.column2type.items())),)
+	msg = f"Testing with types {', '.join((v for k, v in sorted(opts.column2type.items())))}"
 	expect_hl = None
 	if src_ds.hashlabel and opts.column2type.get(src_ds.hashlabel) == 'json':
 		# json is not hashable, so we have to override the hashlabel to nothing in this case.
@@ -222,7 +222,7 @@ def rename(colname):
 	elif src_ds.hashlabel:
 		expect_hl = rename(src_ds.hashlabel)
 		if expect_hl in opts.column2type:
-			msg += ' (hashed on %s)' % (opts.column2type[expect_hl],)
+			msg += f' (hashed on {opts.column2type[expect_hl]})'
 		else:
 			expect_hl = None
 			msg += ' (hashed on )'
@@ -252,7 +252,7 @@ def rename(colname):
 			# not hashable
 			continue
 		opts['hashlabel'] = hashlabel
-		print('%s rehashed on %s' % (msg, opts.column2type[hashlabel],))
+		print(f'{msg} rehashed on {opts.column2type[hashlabel]}')
 		hashed_by_type = subjobs.build('dataset_type', options=opts, datasets=dict(source=src_ds)).dataset()
 		assert hashed_by_type.hashlabel == hashlabel, hashed_by_type
 		assert set(hashed_by_type.columns) == cols, hashed_by_type
diff --git a/accelerator/test_methods/a_test_dataset_type_minmax.py b/accelerator/test_methods/a_test_dataset_type_minmax.py
index f1e1a281..7f91259e 100644
--- a/accelerator/test_methods/a_test_dataset_type_minmax.py
+++ b/accelerator/test_methods/a_test_dataset_type_minmax.py
@@ -167,7 +167,7 @@ def synthesis(job):
 		minmax = (t_ds.columns['v'].min, t_ds.columns['v'].max)
 
 		if minmax != (None, None):
-			raise Exception('Typing empty dataset as %s did not give minmax == None, gave %r' % (typ, minmax,))
+			raise Exception(f'Typing empty dataset as {typ} did not give minmax == None, gave {minmax!r}')
 		all_names = list(chain.from_iterable(groupdata[group].keys() for group in groups))
 		# just 1 and 2, so we don't make way too many
 		for num_groups in (1, 2,):
@@ -176,7 +176,7 @@ def synthesis(job):
 				t_ds = subjobs.build('dataset_type', column2type={'v': typ}, source=ds).dataset()
 				got_minmax = (t_ds.columns['v'].min, t_ds.columns['v'].max)
 				want_minmax = (mn, mx)
-				chk_minmax(got_minmax, want_minmax, 'Typing %s as %s gave wrong minmax: expected %r, got %r (in %s)' % (ds.quoted, typ, want_minmax, got_minmax, t_ds.quoted,))
+				chk_minmax(got_minmax, want_minmax, f'Typing {ds.quoted} as {typ} gave wrong minmax: expected {want_minmax!r}, got {got_minmax!r} (in {t_ds.quoted})')
 				chk_minmax(got_minmax, (t_ds.min('v'), t_ds.max('v')), 'Dataset.min/max() broken on ' + t_ds)
 				# verify writing the same data normally also gives the correct result
 				dw = DatasetWriter(name='rewrite ' + t_ds, columns=t_ds.columns)
@@ -186,7 +186,7 @@ def synthesis(job):
 				re_ds = dw.finish()
 				got_minmax = (re_ds.columns['v'].min, re_ds.columns['v'].max)
 				want_minmax = (mn, mx)
-				chk_minmax(got_minmax, want_minmax, 'Rewriting %s gave the wrong minmax: expected %r, got %r (in %s)' % (t_ds.quoted, want_minmax, got_minmax, re_ds.quoted,))
+				chk_minmax(got_minmax, want_minmax, f'Rewriting {t_ds.quoted} gave the wrong minmax: expected {want_minmax!r}, got {got_minmax!r} (in {re_ds.quoted})')
 
 	# make sure renaming doesn't mix anything up
 	dw = DatasetWriter(name='rename', columns={'a': 'ascii', 'b': 'ascii'})
@@ -206,5 +206,5 @@ def synthesis(job):
 		('int', (2, 3)),
 	):
 		got_minmax = (t_ds.columns[name].min, t_ds.columns[name].max)
-		msg = 'Typing %s gave wrong minmax: expected %r, got %r (in %s)' % (ds.quoted, want_minmax, got_minmax, t_ds.quoted,)
+		msg = f'Typing {ds.quoted} gave wrong minmax: expected {want_minmax!r}, got {got_minmax!r} (in {t_ds.quoted})'
 		chk_minmax(got_minmax, want_minmax, msg)
diff --git a/accelerator/test_methods/a_test_dataset_unroundrobin.py b/accelerator/test_methods/a_test_dataset_unroundrobin.py
index 6a39061c..20d999a7 100644
--- a/accelerator/test_methods/a_test_dataset_unroundrobin.py
+++ b/accelerator/test_methods/a_test_dataset_unroundrobin.py
@@ -50,8 +50,8 @@ def want(a, b):
 		try:
 			got = next(it)
 		except StopIteration:
-			raise Exception('missing lines in %s' % (ds_unrr,))
-		assert got == (a, b), "Wanted %r, got %r from %s" % ((a, b,), got, ds_unrr,)
+			raise Exception(f'missing lines in {ds_unrr}')
+		assert got == (a, b), f"Wanted {(a, b)!r}, got {got!r} from {ds_unrr}"
 	for sliceno in range(slices):
 		want(sliceno, 'u %d' % (sliceno,))
 	for sliceno in range(slices):
@@ -61,7 +61,7 @@ def want(a, b):
 	want(-1, 'line 4 just in slice 0')
 	try:
 		next(it)
-		raise Exception("Extra lines in %s" % (ds_unrr,))
+		raise Exception(f"Extra lines in {ds_unrr}")
 	except StopIteration:
 		pass
 
diff --git a/accelerator/test_methods/a_test_dataset_unroundrobin_trigger.py b/accelerator/test_methods/a_test_dataset_unroundrobin_trigger.py
index d8c98439..50606421 100644
--- a/accelerator/test_methods/a_test_dataset_unroundrobin_trigger.py
+++ b/accelerator/test_methods/a_test_dataset_unroundrobin_trigger.py
@@ -26,7 +26,7 @@
 
 def assert_slice(ds, sliceno, want):
 	got = list(ds.iterate(sliceno))
-	assert got == want, "slice %s in %s (from %s, trigger %s) gave\n\t%r,\nwanted\n\t%r" % (sliceno, ds, ds.job.params.datasets.source, ds.job.params.options.trigger_column, got, want,)
+	assert got == want, f"slice {sliceno} in {ds} (from {ds.job.params.datasets.source}, trigger {ds.job.params.options.trigger_column}) gave\n\t{got!r},\nwanted\n\t{want!r}"
 
 def synthesis(job, slices):
 	unrr_values = [
diff --git a/accelerator/test_methods/a_test_datasetwriter_copy.py b/accelerator/test_methods/a_test_datasetwriter_copy.py
index 9d46d987..565b1d82 100644
--- a/accelerator/test_methods/a_test_datasetwriter_copy.py
+++ b/accelerator/test_methods/a_test_datasetwriter_copy.py
@@ -62,6 +62,6 @@ def synthesis(job, slices, prepare_res):
 	ds = dw_nonetest_removed.finish()
 	for name, col in ds.columns.items():
 		if name == 'unicode':
-			assert col.none_support, "%s:%s should have none_support" % (ds, name,)
+			assert col.none_support, f"{ds}:{name} should have none_support"
 		else:
-			assert not col.none_support, "%s:%s shouldn't have none_support" % (ds, name,)
+			assert not col.none_support, f"{ds}:{name} shouldn't have none_support"
diff --git a/accelerator/test_methods/a_test_datasetwriter_default.py b/accelerator/test_methods/a_test_datasetwriter_default.py
index 0eb424d4..e0345e89 100644
--- a/accelerator/test_methods/a_test_datasetwriter_default.py
+++ b/accelerator/test_methods/a_test_datasetwriter_default.py
@@ -48,7 +48,7 @@ def synthesis(job):
 			try:
 				dw.add('data', t, default=bad_default)
 				dw.get_split_write()
-				raise Exception('%s accepted %r as default value' % (t, bad_default,))
+				raise Exception(f'{t} accepted {bad_default!r} as default value')
 			except (TypeError, ValueError, OverflowError):
 				pass
 			dw.discard()
@@ -61,7 +61,7 @@ def synthesis(job):
 		ds = dw.finish()
 		want = [good_value, default_value, default_value]
 		got = list(ds.iterate(0, 'data'))
-		assert got == want, '%s failed, wanted %r but got %r' % (ds.quoted, want, got,)
+		assert got == want, f'{ds.quoted} failed, wanted {want!r} but got {got!r}'
 
 		dw = job.datasetwriter(name=t + ' default=None', allow_missing_slices=True)
 		dw.add('data', t, default=None, none_support=True)
@@ -72,7 +72,7 @@ def synthesis(job):
 		ds = dw.finish()
 		want = [good_value, None, None]
 		got = list(ds.iterate(0, 'data'))
-		assert got == want, '%s failed, wanted %r but got %r' % (ds.quoted, want, got,)
+		assert got == want, f'{ds.quoted} failed, wanted {want!r} but got {got!r}'
 
 		# make sure default=None hashes correctly
 		if t != 'json':
@@ -85,4 +85,4 @@ def synthesis(job):
 			ds = dw.finish()
 			want = [None, None, None]
 			got = list(ds.iterate(0, 'data'))
-			assert got == want, '%s slice 0 failed, wanted %r but got %r' % (ds.quoted, want, got,)
+			assert got == want, f'{ds.quoted} slice 0 failed, wanted {want!r} but got {got!r}'
diff --git a/accelerator/test_methods/a_test_datasetwriter_parsed.py b/accelerator/test_methods/a_test_datasetwriter_parsed.py
index e2e1c7e7..fa9fb2c0 100644
--- a/accelerator/test_methods/a_test_datasetwriter_parsed.py
+++ b/accelerator/test_methods/a_test_datasetwriter_parsed.py
@@ -38,7 +38,7 @@ def synthesis(job):
 				bad_value = object
 			else:
 				bad_value = 'not valid'
-			name = '%s %s none_support' % (t, 'with' if none_support else 'without',)
+			name = f"{t} {'with' if none_support else 'without'} none_support"
 			dw = job.datasetwriter(name=name, allow_missing_slices=True)
 			dw.add('data', 'parsed:' + t, none_support=none_support)
 			dw.set_slice(0)
@@ -46,11 +46,11 @@ def synthesis(job):
 				dw.write(v)
 			dw.set_slice(1)
 			for v in parse_values:
-				assert isinstance(v, str), 'oops: %r' % (v,)
+				assert isinstance(v, str), f'oops: {v!r}'
 				dw.write(v)
 			try:
 				dw.write(bad_value)
-				raise Exception("parsed:%s accepted %r as a value" % (t, bad_value,))
+				raise Exception(f"parsed:{t} accepted {bad_value!r} as a value")
 			except (ValueError, TypeError):
 				pass
 			# json will of course accept None even without none_support
@@ -59,17 +59,17 @@ def synthesis(job):
 			try:
 				dw.write(None)
 				if not apparent_none_support:
-					raise Exception('parsed:%s accepted None without none_support' % (t,))
+					raise Exception(f'parsed:{t} accepted None without none_support')
 			except (ValueError, TypeError):
 				if apparent_none_support:
-					raise Exception('parsed:%s did not accept None despite none_support' % (t,))
+					raise Exception(f'parsed:{t} did not accept None despite none_support')
 			ds = dw.finish()
 			for sliceno, desc in enumerate(("normal values", "parseable values",)):
 				got = list(ds.iterate(sliceno, 'data'))
-				assert got == values, "parsed:%s (%s) %s gave %r, wanted %r" % (t, ds.quoted, desc, got, values,)
+				assert got == values, f"parsed:{t} ({ds.quoted}) {desc} gave {got!r}, wanted {values!r}"
 			if apparent_none_support:
 				got = list(ds.iterate(2, 'data'))
-				assert got == [None], "parsed:%s (%s) gave %r, wanted [None]" % (t, ds.quoted, got,)
+				assert got == [None], f"parsed:{t} ({ds.quoted}) gave {got!r}, wanted [None]"
 			dw = job.datasetwriter(name=name + ' with default', allow_missing_slices=True)
 			default = None if none_support else 42
 			dw.add('data', 'parsed:' + t, none_support=none_support, default=default)
@@ -78,4 +78,4 @@ def synthesis(job):
 			dw.write(bad_value)
 			ds = dw.finish()
 			got = list(ds.iterate(0, 'data'))
-			assert got == [1, default], "parsed:%s with default=%s (%s) gave %r, wanted [1, %s]" % (t, default, ds.quoted, got, default)
+			assert got == [1, default], f"parsed:{t} with default={default} ({ds.quoted}) gave {got!r}, wanted [1, {default}]"
diff --git a/accelerator/test_methods/a_test_hashlabel.py b/accelerator/test_methods/a_test_hashlabel.py
index 4de35170..9458cff1 100644
--- a/accelerator/test_methods/a_test_hashlabel.py
+++ b/accelerator/test_methods/a_test_hashlabel.py
@@ -106,7 +106,7 @@ def analysis(sliceno, prepare_res, params):
 				good = False
 			except Exception:
 				pass
-			assert good, "%s allowed writing in wrong slice" % (fn,)
+			assert good, f"{fn} allowed writing in wrong slice"
 
 # complex isn't sortable
 def uncomplex(t):
@@ -177,9 +177,9 @@ def synthesis(prepare_res, params, job, slices):
 	):
 		up = cleanup(all_ds[up_name].iterate(None))
 		down = cleanup(all_ds[down_name].iterate(None))
-		assert up != down, "Hashlabel did not change slice distribution (%s vs %s)" % (up_name, down_name)
+		assert up != down, f"Hashlabel did not change slice distribution ({up_name} vs {down_name})"
 		# And check that the data is still the same.
-		assert sorted(up) == sorted(down) == all_data, "Hashed datasets have wrong data (%s vs %s)" % (up_name, down_name)
+		assert sorted(up) == sorted(down) == all_data, f"Hashed datasets have wrong data ({up_name} vs {down_name})"
 
 	# Verify that rehashing works.
 	# (Can't use sliceno None, because that won't rehash, and even if it did
diff --git a/accelerator/test_methods/a_test_hashpart.py b/accelerator/test_methods/a_test_hashpart.py
index 3f340880..c496ae2f 100644
--- a/accelerator/test_methods/a_test_hashpart.py
+++ b/accelerator/test_methods/a_test_hashpart.py
@@ -85,7 +85,7 @@ def verify(slices, data, source, previous=None, **options):
 			row = dict(zip(names, row))
 			assert h(row[hl]) % slices == slice, "row %r is incorrectly in slice %d in %s" % (row, slice, ds)
 			want = good[row[hl]]
-			assert row == want, '%s (rehashed from %s) did not contain the right data for "%s".\nWanted\n%r\ngot\n%r' % (ds, source, hl, want, row)
+			assert row == want, f'{ds} (rehashed from {source}) did not contain the right data for "{hl}".\nWanted\n{want!r}\ngot\n{row!r}'
 	want_lines = len(data)
 	got_lines = ds.chain().lines()
 	assert got_lines == want_lines, '%s (rehashed from %s) had %d lines, should have had %d' % (ds, source, got_lines, want_lines,)
@@ -99,8 +99,8 @@ def verify_empty(source, previous=None, **options):
 	)
 	ds = Dataset(jid)
 	chain = ds.chain_within_job()
-	assert list(chain.iterate(None)) == [], "source=%s previous=%s did not produce empty dataset in %s" % (source, previous, ds,)
-	assert chain[0].previous == previous, "Empty %s should have had previous=%s, but had %s" % (ds, previous, chain[0].previous,)
+	assert list(chain.iterate(None)) == [], f"source={source} previous={previous} did not produce empty dataset in {ds}"
+	assert chain[0].previous == previous, f"Empty {ds} should have had previous={previous}, but had {chain[0].previous}"
 
 def synthesis(params):
 	ds = write(data)
@@ -117,7 +117,7 @@ def synthesis(params):
 	# normal chaining
 	a = verify(params.slices, data, ds, hashlabel="date")
 	b = verify(params.slices, data + bonus_data, bonus_ds, hashlabel="date", previous=a)
-	assert b.chain() == [a, b], "chain of %s is not [%s, %s] as expected" % (b, a, b)
+	assert b.chain() == [a, b], f"chain of {b} is not [{a}, {b}] as expected"
 	# chain_slices sparseness
 	empty = write([], name="empty")
 	verify_empty(empty, hashlabel="date")
diff --git a/accelerator/test_methods/a_test_job_save.py b/accelerator/test_methods/a_test_job_save.py
index 736afbda..b7bec41d 100644
--- a/accelerator/test_methods/a_test_job_save.py
+++ b/accelerator/test_methods/a_test_job_save.py
@@ -25,17 +25,17 @@
 
 
 def save(job, name, sliceno):
-	p = job.save('contents of %s %s' % (name, sliceno,), name + '.pickle', sliceno=sliceno)
+	p = job.save(f'contents of {name} {sliceno}', name + '.pickle', sliceno=sliceno)
 	j = job.json_save({name: sliceno}, name + '.json', sliceno=sliceno)
 	name += '_path'
-	p_path = job.save('contents of %s %s' % (name, sliceno,), Path(name + '.pickle'), sliceno=sliceno)
+	p_path = job.save(f'contents of {name} {sliceno}', Path(name + '.pickle'), sliceno=sliceno)
 	j_path = job.json_save({name: sliceno}, Path(name + '.json'), sliceno=sliceno)
 	return p, j, p_path, j_path
 
 def check(job, name, sliceno, p, j, p_path, j_path):
-	assert p.load() == job.load(Path(p.filename)) == 'contents of %s %s' % (name, sliceno,)
+	assert p.load() == job.load(Path(p.filename)) == f'contents of {name} {sliceno}'
 	assert j.load() == job.json_load(Path(j.filename)) == {name: sliceno}
-	assert p_path.load() == job.load(Path(p_path.filename)) == 'contents of %s_path %s' % (name, sliceno,)
+	assert p_path.load() == job.load(Path(p_path.filename)) == f'contents of {name}_path {sliceno}'
 	assert j_path.load() == job.json_load(Path(j_path.filename)) == {name + '_path': sliceno}
 	for obj, filename in [
 		# Use Path() for files saved with strings and strings for files saved with Path.
diff --git a/accelerator/test_methods/a_test_job_save_background.py b/accelerator/test_methods/a_test_job_save_background.py
index cd9b13a8..5b5f734b 100644
--- a/accelerator/test_methods/a_test_job_save_background.py
+++ b/accelerator/test_methods/a_test_job_save_background.py
@@ -72,14 +72,14 @@ def __bool__(self):
 
 def save(job, name, sliceno):
 	before = monotonic()
-	p = job.save('contents of %s %s' % (name, sliceno,), name + '.pickle', sliceno=sliceno)
+	p = job.save(f'contents of {name} {sliceno}', name + '.pickle', sliceno=sliceno)
 	j = job.json_save({name: sliceno}, name + '.json', sliceno=sliceno)
 	name = 'background ' + name
-	bp = job.save(SlowToPickle('contents of %s %s' % (name, sliceno,), options.sleeptime), name + '.pickle', sliceno=sliceno, background=True)
+	bp = job.save(SlowToPickle(f'contents of {name} {sliceno}', options.sleeptime), name + '.pickle', sliceno=sliceno, background=True)
 	bj = job.json_save({name: sliceno}, name + '.json', sliceno=sliceno, sort_keys=SlowTrue(options.sleeptime), background=True)
 	save_time = monotonic() - before
 	max_time = options.sleeptime * 2 # two slow files
-	assert save_time < max_time, "Saving took %s seconds, should have been less than %s" % (save_time, max_time,)
+	assert save_time < max_time, f"Saving took {save_time} seconds, should have been less than {max_time}"
 	return p, j, bp, bj
 
 def check(job, name, sliceno, p, j, bp, bj, do_background=True, do_wait=False):
@@ -91,7 +91,7 @@ def check(job, name, sliceno, p, j, bp, bj, do_background=True, do_wait=False):
 			# Do explicit waiting sometimes
 			p.wait()
 			j.wait()
-		assert p.load() == 'contents of %s %s' % (name, sliceno,)
+		assert p.load() == f'contents of {name} {sliceno}'
 		assert j.load() == {name: sliceno}
 		for obj, filename in [(p, name + '.pickle'), (j, name + '.json')]:
 			path = job.filename(filename, sliceno=sliceno)
@@ -110,12 +110,12 @@ def prepare(job):
 	p = job.save(SlowToPickle('', checktime), 'test.pickle', background=True)
 	p.wait()
 	pickle_time = monotonic() - before
-	assert pickle_time > checktime, "Saving a slow pickle took %s seconds, should have taken more than %s" % (pickle_time, checktime,)
+	assert pickle_time > checktime, f"Saving a slow pickle took {pickle_time} seconds, should have taken more than {checktime}"
 	before = monotonic()
 	j = job.json_save({}, 'test.json', sort_keys=SlowTrue(checktime), background=True)
 	j.wait()
 	json_time = monotonic() - before
-	assert json_time > checktime, "Saving a slow json took %s seconds, should have taken more than %s" % (json_time, checktime,)
+	assert json_time > checktime, f"Saving a slow json took {json_time} seconds, should have taken more than {checktime}"
 
 	return res
 
diff --git a/accelerator/test_methods/a_test_json.py b/accelerator/test_methods/a_test_json.py
index fe8ad1ad..93093b18 100644
--- a/accelerator/test_methods/a_test_json.py
+++ b/accelerator/test_methods/a_test_json.py
@@ -34,15 +34,15 @@ def test(name, input, want_obj, want_bytes, **kw):
 		got_bytes_raw = got_bytes_raw[:-1]
 	as_str = json_encode(input, as_str=True, **kw)
 	as_bytes = json_encode(input, as_str=False, **kw)
-	assert isinstance(as_str, str) and isinstance(as_bytes, bytes), "json_encode returns the wrong types: %s %s" % (type(as_str), type(as_bytes),)
+	assert isinstance(as_str, str) and isinstance(as_bytes, bytes), f"json_encode returns the wrong types: {type(as_str)} {type(as_bytes)}"
 	assert as_bytes == got_bytes_raw, "json_save doesn't save the same thing json_encode returns for " + name
 	as_str = as_str.encode("utf-8")
 	assert as_bytes == as_str, "json_encode doesn't return the same data for as_str=True and False"
 	got_obj = json_load(name)
-	assert want_obj == got_obj, "%s roundtrips wrong (wanted %r, got %r)" % (name, want_obj, got_obj)
+	assert want_obj == got_obj, f"{name} roundtrips wrong (wanted {want_obj!r}, got {got_obj!r})"
 	with open(name, "rb") as fh:
 		got_bytes_fuzzy = b"".join(line.strip() for line in fh)
-	assert want_bytes == got_bytes_fuzzy, "%s wrong on disk (but decoded right)" % (name,)
+	assert want_bytes == got_bytes_fuzzy, f"{name} wrong on disk (but decoded right)"
 
 def synthesis():
 	test(
@@ -105,7 +105,7 @@ def synthesis():
 		s = "{"
 		for k, v in pairs:
 			d[k] = v
-			s += '"%s": %s,' % (k, v)
+			s += f'"{k}": {v},'
 		s = (s[:-1] + "}").encode("ascii")
 		if not sorted_s:
 			sorted_s = s
diff --git a/accelerator/test_methods/a_test_nan.py b/accelerator/test_methods/a_test_nan.py
index 6c21c2f1..110e6871 100644
--- a/accelerator/test_methods/a_test_nan.py
+++ b/accelerator/test_methods/a_test_nan.py
@@ -68,7 +68,7 @@ def test_encoding_and_hash(typ, nan, *want):
 		with gzip.open('tmp', 'rb') as fh:
 			got_bytes = fh.read()
 		os.remove('tmp')
-		assert got_bytes in want, 'bad NaN representation in %s: got %r, wanted something in %r' % (typ, got_bytes, want,)
+		assert got_bytes in want, f'bad NaN representation in {typ}: got {got_bytes!r}, wanted something in {want!r}'
 
 	# Test that they either encode as themselves or as one of the normal NaNs,
 	# and all hash the same as the standard float64 NaN.
@@ -108,14 +108,14 @@ def mk_dws(typ):
 			w_u(str(ix), v)
 			w_h(str(ix), v)
 		ds_h = dw_h.finish()
-		assert set(ds_h.lines) == {0, len(values)}, 'Not all NaNs ended up in the same slice in %s' % (ds_h.quoted,)
+		assert set(ds_h.lines) == {0, len(values)}, f'Not all NaNs ended up in the same slice in {ds_h.quoted}'
 		expect_lines = ds_h.lines
 		ds_u = dw_u.finish()
 		ds = build('dataset_hashpart', source=ds_u, hashlabel='nan').dataset()
-		assert set(ds.lines) == {0, len(values)}, 'Not all NaNs ended up in the same slice in %s (dataset_hashpart from %s)' % (ds.quoted, ds_u.quoted,)
-		assert expect_lines == ds.lines, 'dataset_hashpart (%s) disagrees with datasetwriter (%s) about NaN slicing' % (ds.quoted, ds_h.quoted,)
+		assert set(ds.lines) == {0, len(values)}, f'Not all NaNs ended up in the same slice in {ds.quoted} (dataset_hashpart from {ds_u.quoted})'
+		assert expect_lines == ds.lines, f'dataset_hashpart ({ds.quoted}) disagrees with datasetwriter ({ds_h.quoted}) about NaN slicing'
 		ds = build('dataset_type', source=ds_u, hashlabel='nan', column2type={'ix': 'number'}).dataset()
-		assert set(ds.lines) == {0, len(values)}, 'Not all NaNs ended up in the same slice in %s (dataset_type from %s)' % (ds.quoted, ds_u.quoted,)
-		assert expect_lines == ds.lines, 'dataset_type (%s) disagrees with datasetwriter (%s) about NaN slicing' % (ds.quoted, ds_h.quoted,)
+		assert set(ds.lines) == {0, len(values)}, f'Not all NaNs ended up in the same slice in {ds.quoted} (dataset_type from {ds_u.quoted})'
+		assert expect_lines == ds.lines, f'dataset_type ({ds.quoted}) disagrees with datasetwriter ({ds_h.quoted}) about NaN slicing'
 		rehash_lines = [len(list(ds_u.iterate(sliceno, rehash=True, hashlabel='nan'))) for sliceno in range(slices)]
-		assert expect_lines == rehash_lines, 'ds.iterate(rehash=True) of %s disagrees with datasetwriter hashing (%s) about NaN slicing' % (ds_u.quoted, ds_h.quoted,)
+		assert expect_lines == rehash_lines, f'ds.iterate(rehash=True) of {ds_u.quoted} disagrees with datasetwriter hashing ({ds_h.quoted}) about NaN slicing'
diff --git a/accelerator/test_methods/a_test_number.py b/accelerator/test_methods/a_test_number.py
index 99185b25..2daad305 100644
--- a/accelerator/test_methods/a_test_number.py
+++ b/accelerator/test_methods/a_test_number.py
@@ -98,7 +98,7 @@ def encode_as_big_number(num):
 		for v in values:
 			value = v[0]
 			write(value)
-			csv_fh.write('%s\n' % (value,))
+			csv_fh.write(f'{value}\n')
 			if len(v) == 1:
 				want_bytes = encode_as_big_number(v[0])
 			else:
@@ -108,7 +108,7 @@ def encode_as_big_number(num):
 				w.write(value)
 			with gzip.open('tmp', 'rb') as fh:
 				got_bytes = fh.read()
-			assert want_bytes == got_bytes, "%r gave %r, wanted %r" % (value, got_bytes, want_bytes,)
+			assert want_bytes == got_bytes, f"{value!r} gave {got_bytes!r}, wanted {want_bytes!r}"
 
 	# Make sure we get the same representation through a dataset.
 	# Assumes that the column is merged (a single file for all slices).
@@ -127,7 +127,7 @@ def encode_as_big_number(num):
 	ds_typed = jid.dataset()
 	with gzip.open(ds_typed.column_filename('num'), 'rb') as fh:
 		got_bytes = fh.read()
-	assert want_bytes == got_bytes, "csvimport + dataset_type (%s) gave different bytes" % (jid,)
+	assert want_bytes == got_bytes, f"csvimport + dataset_type ({jid}) gave different bytes"
 
 	# Also test the hashing is as expected, both in DatasetWriter, dataset_type and dataset_hashpart.
 	def hash_num(num):
diff --git a/accelerator/test_methods/a_test_optionenum.py b/accelerator/test_methods/a_test_optionenum.py
index f7fd0091..fd6eb816 100644
--- a/accelerator/test_methods/a_test_optionenum.py
+++ b/accelerator/test_methods/a_test_optionenum.py
@@ -56,7 +56,7 @@ def check(**options):
 	want_res.update(pass_options)
 	jid = subjobs.build("test_optionenum", options=pass_options)
 	res = blob.load(jobid=jid)
-	assert res == want_res, "%r != %r from %r" % (res, want_res, options,)
+	assert res == want_res, f"{res!r} != {want_res!r} from {options!r}"
 
 def check_unbuildable(**options):
 	try:
@@ -65,7 +65,7 @@ def check_unbuildable(**options):
 		if e.args[0].startswith("Submit failed"):
 			return
 		raise
-	raise Exception("Building with options = %r should have failed but didn't" % (options,))
+	raise Exception(f"Building with options = {options!r} should have failed but didn't")
 
 def synthesis():
 	if options.inner:
diff --git a/accelerator/test_methods/a_test_output.py b/accelerator/test_methods/a_test_output.py
index 97218bbb..06f21da6 100644
--- a/accelerator/test_methods/a_test_output.py
+++ b/accelerator/test_methods/a_test_output.py
@@ -61,8 +61,8 @@ def chk(part):
 		with open(d +  part, 'r') as fh:
 			got = fh.read().replace('\r\n', '\n')
 		want = prefix + '\n' + data + '\n'
-		assert got == prefix + '\n' + data + '\n', "%s produced %r in %s, expected %r" % (jid, got, part, want,)
-		assert output == got, 'job.output disagrees with manual file reading for %s in %s. %r != %r' % (part, jid, output, got,)
+		assert got == prefix + '\n' + data + '\n', f"{jid} produced {got!r} in {part}, expected {want!r}"
+		assert output == got, f'job.output disagrees with manual file reading for {part} in {jid}. {output!r} != {got!r}'
 		all.append(got)
 	if p:
 		chk('prepare')
@@ -72,10 +72,10 @@ def chk(part):
 	if s:
 		chk('synthesis')
 	unchked = set(os.listdir(d)) - chked
-	assert not unchked, "Unexpected OUTPUT files from %s: %r" % (jid, unchked,)
+	assert not unchked, f"Unexpected OUTPUT files from {jid}: {unchked!r}"
 	output = jid.output()
 	got = ''.join(all)
-	assert output == got, 'job.output disagrees with manual file reading for  in %s. %r != %r' % (jid, output, got,)
+	assert output == got, f'job.output disagrees with manual file reading for  in {jid}. {output!r} != {got!r}'
 
 def synthesis(params):
 	test(params, s=True)
@@ -106,7 +106,7 @@ def verify(want):
 			# it might not have reached the server yet
 			timeout += 0.01
 		# we've given it 3 seconds, it's not going to happen.
-		raise Exception("Wanted to see tail output of %r, but saw %r" % (want, got,))
+		raise Exception(f"Wanted to see tail output of {want!r}, but saw {got!r}")
 	print(opts.prefix, file=sys.stderr)
 	verify(opts.prefix + '\n')
 	if isinstance(sliceno, int):
diff --git a/accelerator/test_methods/a_test_output_on_error.py b/accelerator/test_methods/a_test_output_on_error.py
index 148d4414..ba09438a 100644
--- a/accelerator/test_methods/a_test_output_on_error.py
+++ b/accelerator/test_methods/a_test_output_on_error.py
@@ -53,4 +53,4 @@ def synthesis():
 			if attempt > 1:
 				print('Output from %s has not appeared yet, waiting more (%d).' % (job, attempt,))
 			sleep(attempt / 10.0)
-		raise Exception('Not all output from %s was saved in OUTPUT' % (job,))
+		raise Exception(f'Not all output from {job} was saved in OUTPUT')
diff --git a/accelerator/test_methods/a_test_register_file.py b/accelerator/test_methods/a_test_register_file.py
index f6d35540..025f1c37 100644
--- a/accelerator/test_methods/a_test_register_file.py
+++ b/accelerator/test_methods/a_test_register_file.py
@@ -34,11 +34,11 @@ def test(method, *want_files):
 		if want_files != got_files:
 			extra_files = got_files - want_files
 			missing_files = want_files - got_files
-			msg = "Got the wrong files from %s: %r" % (method, got_files,)
+			msg = f"Got the wrong files from {method}: {got_files!r}"
 			if extra_files:
-				msg += ", did not expect %r" % (extra_files,)
+				msg += f", did not expect {extra_files!r}"
 			if missing_files:
-				msg += ", also wanted %r" % (missing_files,)
+				msg += f", also wanted {missing_files!r}"
 			raise Exception(msg)
 
 	test('test_register_file_auto', 'analysis slice 0.txt', 'synthesis file.txt', 'result.pickle')
diff --git a/accelerator/test_methods/a_test_shell_commands.py b/accelerator/test_methods/a_test_shell_commands.py
index 328831fd..9730a7a4 100644
--- a/accelerator/test_methods/a_test_shell_commands.py
+++ b/accelerator/test_methods/a_test_shell_commands.py
@@ -51,12 +51,12 @@ def chk(cmd, want_in_help=[], want_in_call=[], dont_want_in_call=[]):
 		output = ax(args)
 		for want in want_l:
 			if want not in output:
-				print("Expected to find %r in %r output:\n\n%s\n\nbut didn't." % (want, args, output,))
-				raise Exception("Failed in command %r" % (cmd[0],))
+				print(f"Expected to find {want!r} in {args!r} output:\n\n{output}\n\nbut didn't.")
+				raise Exception(f"Failed in command {cmd[0]!r}")
 		for dont_want in dont_want_l:
 			if dont_want in output:
-				print("Did not expect to find %r in %r output:\n\n%s\n\nbut did." % (dont_want, args, output,))
-				raise Exception("Failed in command %r" % (cmd[0],))
+				print(f"Did not expect to find {dont_want!r} in {args!r} output:\n\n{output}\n\nbut did.")
+				raise Exception(f"Failed in command {cmd[0]!r}")
 
 def synthesis(job):
 	print('look for this later')
diff --git a/accelerator/test_methods/a_test_shell_config.py b/accelerator/test_methods/a_test_shell_config.py
index 3e16273b..7876bf9f 100644
--- a/accelerator/test_methods/a_test_shell_config.py
+++ b/accelerator/test_methods/a_test_shell_config.py
@@ -58,10 +58,10 @@ def chk(cfgstr, pre, post):
 		try:
 			got = ax_cmd('job', job).split('\n')[-1]
 		except CalledProcessError as e:
-			raise Exception("%r could not run: %s" % (cfgstr, e,))
-		want = '%sWARNING: Job did not finish%s' % (pre, post,)
+			raise Exception(f"{cfgstr!r} could not run: {e}")
+		want = f'{pre}WARNING: Job did not finish{post}'
 		if got != want:
-			raise Exception("%r:\nWanted %r\ngot    %r" % (cfgstr, want, got,))
+			raise Exception(f"{cfgstr!r}:\nWanted {want!r}\ngot    {got!r}")
 
 	# test the colour config
 	chk('\twarning = CYAN', '\x1b[36m', '\x1b[39m')
diff --git a/accelerator/test_methods/a_test_shell_ds.py b/accelerator/test_methods/a_test_shell_ds.py
index c1112b52..16821da5 100644
--- a/accelerator/test_methods/a_test_shell_ds.py
+++ b/accelerator/test_methods/a_test_shell_ds.py
@@ -45,4 +45,4 @@ def synthesis(job):
 		res = ax_ds(spec)
 		got_ds = res[0]
 		ds = quote(ds)
-		assert ds == got_ds, 'Spec %r should have given %r but gave %r' % (spec, ds, got_ds,)
+		assert ds == got_ds, f'Spec {spec!r} should have given {ds!r} but gave {got_ds!r}'
diff --git a/accelerator/test_methods/a_test_shell_grep.py b/accelerator/test_methods/a_test_shell_grep.py
index 27352cf2..ed615b54 100644
--- a/accelerator/test_methods/a_test_shell_grep.py
+++ b/accelerator/test_methods/a_test_shell_grep.py
@@ -44,7 +44,7 @@ def grep_text(args, want, sep='\t', encoding='utf-8', unordered=False, check_out
 	res = check_output(cmd)
 	res = res.split(b'\n')[:-1]
 	if len(want) != len(res):
-		raise Exception('%r gave %d lines, wanted %d.\n%r' % (cmd, len(res), len(want), res,))
+		raise Exception(f'{cmd!r} gave {len(res)} lines, wanted {len(want)}.\n{res!r}')
 	if encoding:
 		res = [el.decode(encoding, 'replace') for el in res]
 	typ = type(sep)
@@ -81,7 +81,7 @@ def grep_json(args, want):
 	res = res.decode('utf-8', 'surrogatepass')
 	res = res.split('\n')[:-1]
 	if len(want) != len(res):
-		raise Exception('%r gave %d lines, wanted %d.\n%r' % (cmd, len(res), len(want), res,))
+		raise Exception(f'{cmd!r} gave {len(res)} lines, wanted {len(want)}.\n{res!r}')
 	for lineno, (want, got) in enumerate(zip(want, res), 1):
 		try:
 			got = json.loads(got)
@@ -681,7 +681,7 @@ def json_fixup(line):
 		{'dataset': d, 'sliceno': 1, 'lineno': 0, 'data': want_json[1]},
 	])
 	all_types = {n for n in _convfuncs if not n.startswith('parsed:')}
-	assert used_types == all_types, 'Missing/extra column types: %r %r' % (all_types - used_types, used_types - all_types,)
+	assert used_types == all_types, f'Missing/extra column types: {all_types - used_types!r} {used_types - all_types!r}'
 
 	# test the smart tab mode with various lengths
 
@@ -1149,7 +1149,7 @@ def mk_lined_ds(name, *lines, **kw):
 	cmd = options.command_prefix + ['grep', '--unique=c', '--chain', '000', uniq3]
 	try:
 		check_output(cmd)
-		raise Exception("%r worked, should have complained that %s doesn't have column c" % (cmd, uniq.quoted,))
+		raise Exception(f"{cmd!r} worked, should have complained that {uniq.quoted} doesn't have column c")
 	except CalledProcessError:
 		pass
 
diff --git a/accelerator/test_methods/a_test_shell_job.py b/accelerator/test_methods/a_test_shell_job.py
index a315aa3f..1ce5e4f0 100644
--- a/accelerator/test_methods/a_test_shell_job.py
+++ b/accelerator/test_methods/a_test_shell_job.py
@@ -52,4 +52,4 @@ def synthesis(job):
 	for spec, jobid in options.want.items():
 		res = ax_job(spec)
 		got_jobid = res[0].split('/')[-1]
-		assert got_jobid.startswith(jobid), 'Spec %r should have given %r but gave %r' % (spec, jobid, got_jobid,)
+		assert got_jobid.startswith(jobid), f'Spec {spec!r} should have given {jobid!r} but gave {got_jobid!r}'
diff --git a/accelerator/test_methods/a_test_sort_trigger.py b/accelerator/test_methods/a_test_sort_trigger.py
index 099c8d22..60869ff3 100644
--- a/accelerator/test_methods/a_test_sort_trigger.py
+++ b/accelerator/test_methods/a_test_sort_trigger.py
@@ -28,7 +28,7 @@
 def sort(src, ix, **kw):
 	ds = subjobs.build('dataset_sort', source=src, sort_across_slices=True, **kw).dataset()
 	want = sorted(src.iterate(None), key=itemgetter(ix))
-	assert list(ds.iterate(None)) == want, '%s != sorted(%s)' % (ds, src,)
+	assert list(ds.iterate(None)) == want, f'{ds} != sorted({src})'
 	return ds
 
 def synthesis(job):
@@ -47,14 +47,14 @@ def synthesis(job):
 	src = dw.finish()
 	# Unchanging trigger
 	a = sort(src, 0, sort_columns='a', trigger_column='a')
-	assert set(a.lines) == {0, 60}, '%s %r' % (a, a.lines,)
+	assert set(a.lines) == {0, 60}, f'{a} {a.lines!r}'
 	# Just two trigger values
 	b = sort(src, 1, sort_columns='b', trigger_column='b')
-	assert set(b.lines) == {0, 30}, '%s %r' % (b, b.lines,)
+	assert set(b.lines) == {0, 30}, f'{b} {b.lines!r}'
 	# Trigger value changes every time - trigger_column should affect nothing
 	c = sort(src, 2, sort_columns='c')
 	ct = sort(src, 2, sort_columns='c', trigger_column='c')
-	assert c.lines == ct.lines, '%s %r != %s %r' % (c, c.lines, ct, ct.lines,)
+	assert c.lines == ct.lines, f'{c} {c.lines!r} != {ct} {ct.lines!r}'
 	# check that using second sort column as trigger works
 	bc = sort(src, 2, sort_columns=['c', 'b'], trigger_column='b')
-	assert set(bc.lines) == {0, 30}, '%s %r' % (bc, bc.lines,)
+	assert set(bc.lines) == {0, 30}, f'{bc} {bc.lines!r}'
diff --git a/accelerator/test_methods/a_test_sorting.py b/accelerator/test_methods/a_test_sorting.py
index e832fc21..1d95ecaa 100644
--- a/accelerator/test_methods/a_test_sorting.py
+++ b/accelerator/test_methods/a_test_sorting.py
@@ -109,4 +109,4 @@ def synthesis(params):
 	good = sorted(all_data, key=lambda t: (noneninf(t[int64_off]), noneninf(t[int32_off]),), reverse=True)
 	ds = Dataset(jid)
 	check = list(ds.iterate(None))
-	assert unnan(check) == unnan(good), "Sorting across slices on [int64, int32] bad (%s)" % (jid,)
+	assert unnan(check) == unnan(good), f"Sorting across slices on [int64, int32] bad ({jid})"
diff --git a/accelerator/test_methods/a_test_urd.py b/accelerator/test_methods/a_test_urd.py
index 3c348908..34f28e63 100644
--- a/accelerator/test_methods/a_test_urd.py
+++ b/accelerator/test_methods/a_test_urd.py
@@ -67,7 +67,7 @@ def synthesis(job):
 	headers = {'Content-Type': 'application/json', 'Authorization': 'Basic dGVzdDpwYXNz'}
 	def check(url_part, want, post_data=None):
 		got = call(url + url_part, server_name='urd', data=post_data, headers=headers, fmt=json.loads)
-		assert want == got, '\nWanted %r,\ngot    %r' % (want, got,)
+		assert want == got, f'\nWanted {want!r},\ngot    {got!r}'
 
 	check('list', ['test/ing', 'test/two'])
 	check('test/ing/since/0', ['2023-01', '2023-02', '2023-06', '2024-03'])
@@ -126,7 +126,7 @@ def check(url_part, want, post_data=None):
 		for got, want in zip(fh, want_it):
 			assert got.startswith('4\t'), got
 			got = got.split('\t', 2)[2]
-			assert want == got, '\nWanted %r,\ngot    %r' % (want, got,)
+			assert want == got, f'\nWanted {want!r},\ngot    {got!r}'
 		assert next(want_it) == 'END'
 
 	p.terminate()
diff --git a/accelerator/test_methods/build_tests.py b/accelerator/test_methods/build_tests.py
index 5d8f23a1..67d945a2 100644
--- a/accelerator/test_methods/build_tests.py
+++ b/accelerator/test_methods/build_tests.py
@@ -80,14 +80,14 @@ def main(urd):
 	assert fin == {'new': False, 'changed': False, 'is_ghost': False}, fin
 	urd.begin("tests.urd", 1) # will be overridden to 2 in finish
 	jl = urd.latest("tests.urd").joblist
-	assert jl == [job], '%r != [%r]' % (jl, job,)
+	assert jl == [job], f'{jl!r} != [{job!r}]'
 	urd.build("test_build_kws", options=dict(foo='bar', a='A'))
 	urd.finish("tests.urd", 2, caption="second")
 	u = urd.peek_latest("tests.urd")
 	assert u.caption == "second"
 	dep0 = list(u.deps.values())[0]
 	assert dep0.caption == "first", dep0.caption
-	assert dep0.joblist == jl, '%r != %r' % (dep0.joblist, jl,)
+	assert dep0.joblist == jl, f'{dep0.joblist!r} != {jl!r}'
 	assert urd.since("tests.urd", 0) == ['1', '2']
 	urd.truncate("tests.urd", 2)
 	assert urd.since("tests.urd", 0) == ['1']
@@ -125,11 +125,11 @@ def main(urd):
 
 	for how in ("exiting", "dying",):
 		print()
-		print("Verifying that an analysis process %s kills the job" % (how,))
+		print(f"Verifying that an analysis process {how} kills the job")
 		time_before = monotonic()
 		try:
 			job = urd.build("test_analysis_died", how=how)
-			print("test_analysis_died completed successfully (%s), that shouldn't happen" % (job,))
+			print(f"test_analysis_died completed successfully ({job}), that shouldn't happen")
 			exit(1)
 		except JobError:
 			time_after = monotonic()
@@ -140,7 +140,7 @@ def main(urd):
 		elif time_to_die > 2:
 			print("test_analysis_died took %d seconds to die, so death detection is slow, but works" % (time_to_die,))
 		else:
-			print("test_analysis_died took %.1f seconds to die, so death detection works" % (time_to_die,))
+			print(f"test_analysis_died took {time_to_die:.1f} seconds to die, so death detection works")
 
 	print()
 	print("Testing dataset creation, export, import")
diff --git a/accelerator/unixhttp.py b/accelerator/unixhttp.py
index 6c8b55a9..72cdb0ef 100644
--- a/accelerator/unixhttp.py
+++ b/accelerator/unixhttp.py
@@ -84,7 +84,7 @@ def call(url, data=None, fmt=json_decode, headers={}, server_name='server', retr
 					s_version = r.headers['Accelerator-Version'] or ''
 					if s_version != ax_version:
 						# Nothing is supposed to catch this, so just print and die.
-						print('Server is running version %s but we are running version %s' % (s_version, ax_version,), file=sys.stderr)
+						print(f'Server is running version {s_version} but we are running version {ax_version}', file=sys.stderr)
 						exit(1)
 				resp = resp.decode('utf-8')
 				# It is inconsistent if we get HTTPError or not.
@@ -115,9 +115,9 @@ def call(url, data=None, fmt=json_decode, headers={}, server_name='server', retr
 			if attempt < retries - 1:
 				msg = None
 			else:
-				msg = 'error contacting %s: %s' % (server_name, e.reason)
+				msg = f'error contacting {server_name}: {e.reason}'
 		except ValueError as e:
-			msg = 'Bad data from %s, %s: %s' % (server_name, type(e).__name__, e,)
+			msg = f'Bad data from {server_name}, {type(e).__name__}: {e}'
 		if msg and not quiet:
 			print(msg, file=sys.stderr)
 		if attempt < retries + 1:
diff --git a/accelerator/urd.py b/accelerator/urd.py
index 4e2fa685..be38f85c 100644
--- a/accelerator/urd.py
+++ b/accelerator/urd.py
@@ -73,7 +73,7 @@ class TimeStamp(str):
 	def __new__(cls, ts):
 		if isinstance(ts, TimeStamp):
 			return ts
-		assert ts, 'Invalid timestamp %s' % (ts,)
+		assert ts, f'Invalid timestamp {ts}'
 		parts = []
 		str_parts = []
 		for part in ts.split('+'):
@@ -86,7 +86,7 @@ def __new__(cls, ts):
 			except ValueError:
 				pass
 			m = re.match(r'(\d{4}-\d{2}(?:-\d{2}(?:[T ]\d{2}(?::\d{2}(?::\d{2}(?:\.\d{1,6})?)?)?)?)?)$', part)
-			assert m, 'Invalid timestamp %s' % (part,)
+			assert m, f'Invalid timestamp {part}'
 			part = part.replace(' ', 'T')
 			parts.append((1, part,))
 			str_parts.append(part)
@@ -175,7 +175,7 @@ def __init__(self, path, verbose=True):
 					print("%-30s  %7d    %7d    %7d" % (key, val, len(self.ghost_db[key]), len(self.db[key]),))
 				print()
 		else:
-			print("Creating directory \"%s\"." % (path,))
+			print(f"Creating directory \"{path}\".")
 			os.makedirs(path)
 		self._lasttime = None
 		self._initialised = True
@@ -251,7 +251,7 @@ def _serialise(self, action, data):
 			json_joblist = json.dumps(data.joblist)
 			json_caption = json.dumps(data.caption)
 			json_build_job = json.dumps(data.build_job)
-			key = '%s/%s' % (data.user, data.build,)
+			key = f'{data.user}/{data.build}'
 			flags = ','.join(data.flags)
 			for s in key, json_deps, json_joblist, json_caption, data.user, data.build, data.timestamp, flags:
 				assert '\t' not in s, s
@@ -283,9 +283,9 @@ def _is_ghost(self, data):
 
 	@locked
 	def add(self, data):
-		key = '%s/%s' % (data.user, data.build)
+		key = f'{data.user}/{data.build}'
 		flags = data.pop('flags', [])
-		assert flags in ([], ['update']), 'Unknown flags: %r' % (flags,)
+		assert flags in ([], ['update']), f'Unknown flags: {flags!r}'
 		new = False
 		changed = False
 		ghosted = 0
@@ -307,7 +307,7 @@ def add(self, data):
 			else:
 				new = True
 		if changed and 'update' not in flags:
-			assert self._initialised, 'Log updates without update flag: %r' % (data,)
+			assert self._initialised, f'Log updates without update flag: {data!r}'
 			bottle.response.status = 409
 			return {'error': 'would update'}
 		if new or changed:
@@ -396,7 +396,7 @@ def log(self, action, data):
 							extra = "  Also failed to remove partially written data."
 							stars = colour.red('****')
 							extra2 = "  " + stars + " YOUR URD DB IS PROBABLY BROKEN NOW! " + stars
-						msg = "  Failed to write %s: %s" % (fn, e)
+						msg = f"  Failed to write {fn}: {e}"
 						brk = "#" * (max(len(msg), len(extra)) + 2)
 						print("", file=sys.stderr)
 						print(brk, file=sys.stderr)
@@ -600,7 +600,7 @@ def main(argv, cfg):
 	authdict = readauth(auth_fn)
 	allow_passwordless = args.allow_passwordless
 	if not authdict and not args.allow_passwordless:
-		raise Exception('No users in %r and --allow-passwordless not specified.' % (auth_fn,))
+		raise Exception(f'No users in {auth_fn!r} and --allow-passwordless not specified.')
 	db = DB(args.path, not args.quiet)
 
 	bottle.install(jsonify)
diff --git a/accelerator/workspace.py b/accelerator/workspace.py
index d2b354e7..860d6f18 100644
--- a/accelerator/workspace.py
+++ b/accelerator/workspace.py
@@ -45,7 +45,7 @@ def _check_metafile(self):
 		""" verify or write metadata file in workdir """
 		filename = os.path.join(self.path, ".slices")
 		if not os.path.isdir(self.path):
-			print('\nERROR:  Directory \"%s\" does not exist!' % (self.path,))
+			print(f'\nERROR:  Directory "{self.path}" does not exist!')
 			return False
 		if not os.path.exists(filename):
 			print('\nCreate ' + filename)
@@ -58,7 +58,7 @@ def _check_metafile(self):
 		with open(filename) as F:
 			file_slices = int(F.read())
 		if file_slices != self.slices:
-			print('\nERROR:  Number of slices in workdir \"%s\" differs from config file!' % (self.name,))
+			print(f'\nERROR:  Number of slices in workdir "{self.name}" differs from config file!')
 			return False
 		return True
 
@@ -100,7 +100,7 @@ def allocate_jobs(self, num_jobs):
 		jobidv = [Job._create(self.name, highest + 1 + x) for x in range(num_jobs)]
 		for jobid in jobidv:
 			fullpath = os.path.join(self.path, jobid)
-			print("WORKDIR:  Allocate_job \"%s\"" % fullpath)
+			print(f"WORKDIR:  Allocate_job \"{fullpath}\"")
 			self.known_jobids.add(jobid)
 			os.mkdir(fullpath)
 		return jobidv
diff --git a/dsutil/test.py b/dsutil/test.py
index 44e6e87a..f47031b7 100755
--- a/dsutil/test.py
+++ b/dsutil/test.py
@@ -90,7 +90,7 @@ def can_minmax(name):
 				if typ is w_typ:
 					# File is not created until written.
 					fh.flush()
-			raise Exception("%r does not give IOError for DOES/NOT/EXIST" % (typ,))
+			raise Exception(f"{typ!r} does not give IOError for DOES/NOT/EXIST")
 		except IOError:
 			pass
 		try:
@@ -99,7 +99,7 @@ def can_minmax(name):
 		except TypeError:
 			pass
 		except Exception:
-			raise Exception("%r does not give TypeError for bad keyword argument" % (typ,))
+			raise Exception(f"{typ!r} does not give TypeError for bad keyword argument")
 	# test that the right data fails to write
 	for test_none_support in (False, True):
 		with w_mk(TMP_FN, none_support=test_none_support) as fh:
@@ -118,8 +118,8 @@ def can_minmax(name):
 			if can_minmax(name):
 				want_min = min(filter(lambda x: x is not None, res_data))
 				want_max = max(filter(lambda x: x is not None, res_data))
-				assert fh.min == want_min, "%s: claims min %r, not %r" % (name, fh.min, want_min,)
-				assert fh.max == want_max, "%s: claims max %r, not %r" % (name, fh.max, want_max,)
+				assert fh.min == want_min, f"{name}: claims min {fh.min!r}, not {want_min!r}"
+				assert fh.max == want_max, f"{name}: claims max {fh.max!r}, not {want_max!r}"
 	# Okay, errors look good
 	with r_mk(TMP_FN) as fh:
 		res = list(fh)
@@ -149,7 +149,7 @@ def can_minmax(name):
 						fh.write(value)
 						count += 1
 					except (ValueError, TypeError, OverflowError):
-						assert 0, "No default: %r" % (value,)
+						assert 0, f"No default: {value!r}"
 				assert fh.count == count, "%s: %d lines written, claims %d" % (name, count, fh.count,)
 			# No errors when there is a default
 			with r_mk(TMP_FN) as fh:
@@ -182,8 +182,8 @@ def slice_test(slices, spread_None):
 				tmp = list(fh)
 			assert len(tmp) == count, "%s (%d, %d): %d lines written, claims %d" % (name, sliceno, slices, len(tmp), count,)
 			for v in tmp:
-				assert (spread_None and v is None) or w_typ.hash(v) % slices == sliceno, "Bad hash for %r" % (v,)
-				assert w_typ.hash(v) == _dsutil.hash(v), "Inconsistent hash for %r" % (v,)
+				assert (spread_None and v is None) or w_typ.hash(v) % slices == sliceno, f"Bad hash for {v!r}"
+				assert w_typ.hash(v) == _dsutil.hash(v), f"Inconsistent hash for {v!r}"
 			res.extend(tmp)
 			sliced_res.append(tmp)
 			if can_minmax(name):
@@ -241,7 +241,7 @@ def slice_test(slices, spread_None):
 
 print("Hash testing, false things")
 for v in (None, "", b"", 0, 0.0, False,):
-	assert _dsutil.hash(v) == 0, "%r doesn't hash to 0" % (v,)
+	assert _dsutil.hash(v) == 0, f"{v!r} doesn't hash to 0"
 print("Hash testing, strings")
 for v in ("", "a", "0", "foo", "a slightly longer string", "\0", "a\0b",):
 	l_u = _dsutil.WriteUnicode.hash(v)
@@ -250,7 +250,7 @@ def slice_test(slices, spread_None):
 	u = _dsutil.WriteUnicode.hash(v)
 	a = _dsutil.WriteAscii.hash(v)
 	b = _dsutil.WriteBytes.hash(v.encode("utf-8"))
-	assert u == l_u == a == l_a == b == l_b, "%r doesn't hash the same" % (v,)
+	assert u == l_u == a == l_a == b == l_b, f"{v!r} doesn't hash the same"
 assert _dsutil.hash(b"\xe4") != _dsutil.hash("\xe4"), "Unicode hash fail"
 assert _dsutil.WriteBytes.hash(b"\xe4") != _dsutil.WriteUnicode.hash("\xe4"), "Unicode hash fail"
 try:
diff --git a/scripts/templates/a_check.py b/scripts/templates/a_check.py
index d8b42770..15a26eda 100644
--- a/scripts/templates/a_check.py
+++ b/scripts/templates/a_check.py
@@ -11,7 +11,7 @@ def check(num, *want):
 		assert job.params.versions.accelerator
 	ds = job.dataset()
 	want_lines = [len(w) for w in want]
-	assert ds.lines == want_lines, '%s should have had %r lines but has %r' % (ds, want_lines, ds.lines,)
+	assert ds.lines == want_lines, f'{ds} should have had {want_lines!r} lines but has {ds.lines!r}'
 	for sliceno, want in enumerate(want):
 		got = list(ds.iterate(sliceno, ('a', 'b',)))
 		assert got == want, '%s slice %d should have had %r but had %r' % (ds, sliceno, want, got,)
@@ -38,7 +38,7 @@ def synthesis(job):
 	# Test for accidental recursion.
 	sys.setrecursionlimit(49)
 	ds51 = Job('%s-%d' % (options.prefix, 51)).dataset()
-	assert len(ds51.chain()) == 50, '%s should have had a dataset chain of length 50' % (job,)
+	assert len(ds51.chain()) == 50, f'{job} should have had a dataset chain of length 50'
 	# And check the chain actually contains the expected stuff (i.e. nothing past the first ds).
 	# (Also to check that iterating the chain doesn't recurse more.)
 	ds2 = Job('%s-%d' % (options.prefix, 2)).dataset()
diff --git a/setup.py b/setup.py
index 774dd52d..c159d989 100755
--- a/setup.py
+++ b/setup.py
@@ -76,7 +76,7 @@ def dirty():
 			assert re.match(r'20\d\d\.\d\d\.\d\d\.(?:dev|rc)\d+$', env_version)
 			version = env_version
 		else:
-			version = "%s.dev1+%s%s" % (version, commit[:10], dirty(),)
+			version = f"{version}.dev1+{commit[:10]}{dirty()}"
 	version = version.replace('.0', '.')
 	with open('accelerator/version.txt', 'w') as fh:
 		fh.write(version + '\n')

From c5a09a532ceda3a8da3dca947ac1c60129419836 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?=
 
Date: Tue, 19 Aug 2025 17:56:46 +0200
Subject: [PATCH 14/18] Migrate all old-style "%" formatting of strings to
 f-strings

This has been done automatically using flynt:
https://github.com/ikamensh/flynt

It is using aggressive mode with some later fixups to fix issues.
---
 accelerator/build.py                          |  8 ++--
 accelerator/configfile.py                     |  2 +-
 accelerator/database.py                       |  2 +-
 accelerator/dataset.py                        | 48 +++++++++----------
 accelerator/dsutil.py                         |  2 +-
 .../examples/a_example_writeslicedfile.py     |  2 +-
 accelerator/extras.py                         | 12 ++---
 accelerator/job.py                            |  4 +-
 accelerator/launch.py                         | 14 +++---
 accelerator/methods.py                        |  2 +-
 accelerator/mp.py                             |  4 +-
 accelerator/runner.py                         |  6 +--
 accelerator/server.py                         |  8 ++--
 accelerator/setupfile.py                      |  2 +-
 accelerator/shell/__init__.py                 |  2 +-
 accelerator/shell/ds.py                       |  2 +-
 accelerator/shell/grep.py                     | 12 ++---
 accelerator/shell/hist.py                     |  2 +-
 accelerator/shell/init.py                     | 12 ++---
 accelerator/shell/job.py                      |  6 +--
 accelerator/shell/parser.py                   |  8 ++--
 accelerator/standard_methods/a_csvexport.py   |  4 +-
 accelerator/standard_methods/a_csvimport.py   |  4 +-
 .../standard_methods/a_csvimport_zip.py       |  2 +-
 .../standard_methods/a_dataset_hashpart.py    |  4 +-
 .../standard_methods/a_dataset_sort.py        |  2 +-
 .../standard_methods/a_dataset_type.py        | 30 ++++++------
 accelerator/standard_methods/dataset_type.py  |  2 +-
 accelerator/statmsg.py                        | 14 +++---
 .../test_methods/a_test_compare_datasets.py   |  4 +-
 .../a_test_csvimport_corner_cases.py          |  8 ++--
 .../a_test_csvimport_separators.py            |  6 +--
 .../test_methods/a_test_csvimport_slicing.py  | 12 ++---
 .../test_methods/a_test_dataset_checksum.py   |  2 +-
 .../a_test_dataset_column_names.py            |  8 ++--
 .../test_methods/a_test_dataset_concat.py     |  4 +-
 .../test_methods/a_test_dataset_fanout.py     |  2 +-
 .../a_test_dataset_parsing_writer.py          |  2 +-
 .../a_test_dataset_rename_columns.py          |  2 +-
 .../a_test_dataset_type_chaining.py           |  4 +-
 .../a_test_dataset_type_corner_cases.py       |  6 +--
 .../a_test_dataset_type_hashing.py            |  8 ++--
 .../a_test_dataset_unroundrobin.py            |  6 +--
 accelerator/test_methods/a_test_hashlabel.py  |  8 ++--
 accelerator/test_methods/a_test_hashpart.py   |  6 +--
 accelerator/test_methods/a_test_json.py       |  4 +-
 accelerator/test_methods/a_test_nan.py        |  2 +-
 accelerator/test_methods/a_test_number.py     |  2 +-
 accelerator/test_methods/a_test_output.py     |  4 +-
 .../test_methods/a_test_output_on_error.py    |  4 +-
 accelerator/test_methods/a_test_rechain.py    |  4 +-
 accelerator/test_methods/a_test_shell_grep.py | 10 ++--
 accelerator/test_methods/a_test_sorting.py    |  2 +-
 .../a_test_status_in_exceptions.py            |  2 +-
 accelerator/test_methods/build_tests.py       |  6 +--
 accelerator/unixhttp.py                       |  4 +-
 accelerator/urd.py                            |  4 +-
 dsutil/test.py                                | 26 +++++-----
 scripts/templates/a_check.py                  |  8 ++--
 scripts/templates/a_verify.py                 |  8 ++--
 60 files changed, 200 insertions(+), 200 deletions(-)

diff --git a/accelerator/build.py b/accelerator/build.py
index 841a06e4..5eec09f5 100644
--- a/accelerator/build.py
+++ b/accelerator/build.py
@@ -173,7 +173,7 @@ def wait(self, ignore_old_errors=False):
 					sys.stdout.write('\r\033[K           %s %s %s' % current_display)
 			idle, now, status_stacks, current, last_time = self._server_idle(1)
 		if self.verbose == 'dots':
-			print('(%d)]' % (last_time,))
+			print(f'({last_time})]')
 		elif self.verbose:
 			print(f'\r\x1b[K              {fmttime(last_time)}')
 
@@ -277,7 +277,7 @@ def call_method(self, method, options={}, datasets={}, jobs={}, record_as=None,
 			print()
 			from inspect import stack
 			stk = stack()[2]
-			print("Called from %s line %d" % (stk[1], stk[2],))
+			print(f"Called from {stk[1]} line {stk[2]}")
 			exit()
 		jid = Job(jid, record_as or method)
 		self.joblist_all.append(jid)
@@ -971,6 +971,6 @@ def print_minimal_traceback():
 	lineno = last_interesting.tb_lineno
 	filename = last_interesting.tb_frame.f_code.co_filename
 	if isinstance(e, JobError):
-		print("Failed to build job %s on %s line %d" % (e.job, filename, lineno,))
+		print(f"Failed to build job {e.job} on {filename} line {lineno}")
 	else:
-		print("Server returned error on %s line %d:\n%s" % (filename, lineno, e.args[0]))
+		print(f"Server returned error on {filename} line {lineno}:\n{e.args[0]}")
diff --git a/accelerator/configfile.py b/accelerator/configfile.py
index 84dab430..7de507a1 100644
--- a/accelerator/configfile.py
+++ b/accelerator/configfile.py
@@ -253,7 +253,7 @@ def everything(key, val):
 		if lineno[0] is None:
 			prefix = f'Error in {filename}:\n'
 		else:
-			prefix = 'Error on line %d of %s:\n' % (lineno[0], filename,)
+			prefix = f'Error on line {lineno[0]} of {filename}:\n'
 		raise UserError(prefix + e.args[0])
 
 	res.config_filename = os.path.realpath(filename)
diff --git a/accelerator/database.py b/accelerator/database.py
index 4de204b2..46220182 100644
--- a/accelerator/database.py
+++ b/accelerator/database.py
@@ -173,7 +173,7 @@ def _update_finish(self, dict_of_hashes, verbose=False):
 		if verbose:
 			if discarded_due_to_hash_list:
 				print(f"DATABASE:  discarding due to unknown hash: {', '.join(discarded_due_to_hash_list)}")
-			print("DATABASE:  Full database contains %d items" % (sum(len(v) for v in itervalues(self.db_by_method)),))
+			print(f"DATABASE:  Full database contains {sum((len(v) for v in itervalues(self.db_by_method)))} items")
 
 	def match_complex(self, reqlist):
 		for method, uid, opttuple in reqlist:
diff --git a/accelerator/dataset.py b/accelerator/dataset.py
index 4d2edeab..df02c938 100644
--- a/accelerator/dataset.py
+++ b/accelerator/dataset.py
@@ -645,16 +645,16 @@ def iterate_list(sliceno, columns, datasets, range=None, sloppy_range=False, has
 				total_lines = sum(sum(d.lines) for d in datasets)
 			if slice.start < 0:
 				if -slice.start > total_lines:
-					raise DatasetUsageError("Wanted last %d lines, but only %d lines available" % (-slice.start, total_lines,))
+					raise DatasetUsageError(f"Wanted last {-slice.start} lines, but only {total_lines} lines available")
 				slice = builtins.slice(total_lines + slice.start, slice.stop, slice.step)
 			if (slice.stop or 0) < 0:
 				if -slice.stop > total_lines:
-					raise DatasetUsageError("Wanted to stop %d lines before end, but only %d lines available" % (-slice.stop, total_lines,))
+					raise DatasetUsageError(f"Wanted to stop {-slice.stop} lines before end, but only {total_lines} lines available")
 				slice = builtins.slice(slice.start, total_lines + slice.stop, slice.step)
 			if slice.start > total_lines:
-				raise DatasetUsageError("Wanted to skip %d lines, but only %d lines available" % (slice.start, total_lines,))
+				raise DatasetUsageError(f"Wanted to skip {slice.start} lines, but only {total_lines} lines available")
 			if (slice.stop or 0) > total_lines:
-				raise DatasetUsageError("Wanted to stop after %d lines, but only %d lines available" % (slice.stop, total_lines,))
+				raise DatasetUsageError(f"Wanted to stop after {slice.stop} lines, but only {total_lines} lines available")
 			if slice.start == total_lines:
 				return iter(())
 			if slice.stop is not None:
@@ -774,12 +774,12 @@ def _resolve_filters(columns, filters, want_tuple):
 			for ix, f in filters:
 				if f is None or f is bool:
 					# use value directly
-					fs.append('t[%d]' % (ix,))
+					fs.append(f't[{ix}]')
 				else:
-					n = 'f%d' % (ix,)
+					n = f'f{ix}'
 					arg_n.append(n)
 					arg_v.append(f)
-					fs.append('%s(t[%d])' % (n, ix,))
+					fs.append(f'{n}(t[{ix}])')
 			f = 'lambda t: ' + ' and '.join(fs)
 			# Add another lambda to put all fN into local variables.
 			# (This is faster than putting them in "locals", you get
@@ -821,7 +821,7 @@ def update_status(ix, d, sliceno, rehash):
 		else:
 			msg_head = f'Iterating {fmt_dsname(*to_iter[0])} to {fmt_dsname(*to_iter[-1])}'
 			def update_status(ix, d, sliceno, rehash):
-				update('%s, %d/%d (%s)' % (msg_head, ix, len(to_iter), fmt_dsname(d, sliceno, rehash)))
+				update(f'{msg_head}, {ix}/{len(to_iter)} ({fmt_dsname(d, sliceno, rehash)})')
 		with status(msg_head) as update:
 			update_status._line_report = getattr(update, '_line_report', None)
 			yield update_status
@@ -1084,7 +1084,7 @@ def getsize(sliceno):
 				if size:
 					with open(fn(sliceno), 'rb') as p_fh:
 						data = p_fh.read()
-					assert len(data) == size, "Slice %d is %d bytes, not %d?" % (sliceno, len(data), size,)
+					assert len(data) == size, f"Slice {sliceno} is {len(data)} bytes, not {size}?"
 					m_fh.write(data)
 					offsets.append(pos)
 				else:
@@ -1338,7 +1338,7 @@ def set_slice(self, sliceno):
 		from accelerator import g
 		if g.running == 'analysis' and self._for_single_slice != g.sliceno:
 			if self._for_single_slice is not None:
-				raise DatasetUsageError("This writer is for slice %d" % (self._for_single_slice,))
+				raise DatasetUsageError(f"This writer is for slice {self._for_single_slice}")
 			else:
 				raise DatasetUsageError("Only use set_slice in analysis together with for_single_slice")
 		self._set_slice(sliceno)
@@ -1348,7 +1348,7 @@ def _set_slice(self, sliceno):
 		if self._started == 2:
 			raise DatasetUsageError("Don't use both set_slice and a split writer")
 		if not isinstance(sliceno, int_types) or sliceno < 0 or sliceno >= slices:
-			raise DatasetUsageError("sliceno must be int in range(%d)" % (slices,))
+			raise DatasetUsageError(f"sliceno must be int in range({slices})")
 		self.close()
 		self.sliceno = sliceno
 		writers = self._mkwriters(sliceno)
@@ -1359,7 +1359,7 @@ def _set_slice(self, sliceno):
 	def column_filename(self, colname, sliceno=None):
 		if sliceno is None:
 			sliceno = self.sliceno
-		return '%s/%d.%s' % (self.fs_name, sliceno, self._filenames[colname],)
+		return f'{self.fs_name}/{sliceno}.{self._filenames[colname]}'
 
 	def enable_hash_discard(self):
 		"""Make the write functions silently discard data that does not
@@ -1427,7 +1427,7 @@ def write_dict(values):
 			hix = -1
 		used_names = set()
 		names = [_clean_name(n, used_names) for n in self._order]
-		w_names = [_clean_name('w%d' % (ix,), used_names) for ix in range(len(w_l))]
+		w_names = [_clean_name(f'w{ix}', used_names) for ix in range(len(w_l))]
 		w_d = dict(zip(w_names, w_l))
 		errcls = _clean_name('DatasetUsageError', used_names)
 		w_d[errcls] = DatasetUsageError
@@ -1439,11 +1439,11 @@ def write_dict(values):
 		else:
 			if hl is not None:
 				f.append(f' if {w_names[hix]}({names[hix]}):')
-				f_list.append(' if %s(values[%d]):' % (w_names[hix], hix,))
+				f_list.append(f' if {w_names[hix]}(values[{hix}]):')
 			for ix in range(len(names)):
 				if ix != hix:
 					f.append(f'  {w_names[ix]}({names[ix]})')
-					f_list.append('  %s(values[%d])' % (w_names[ix], ix,))
+					f_list.append(f'  {w_names[ix]}(values[{ix}])')
 			if hl is not None and not discard:
 				f.append(f' else: raise {errcls}({wrong_slice_msg!r})')
 				f_list.append(f' else: raise {errcls}({wrong_slice_msg!r})')
@@ -1475,7 +1475,7 @@ def _mksplit(self):
 			raise DatasetUsageError("Don't try to use writer after .finish()ing it")
 		if g.running == 'analysis' and self._for_single_slice != g.sliceno:
 			if self._for_single_slice is not None:
-				raise DatasetUsageError("This writer is for slice %d" % (self._for_single_slice,))
+				raise DatasetUsageError(f"This writer is for slice {self._for_single_slice}")
 			else:
 				raise DatasetUsageError("Only use a split writer in analysis together with for_single_slice")
 		if self._started == 1:
@@ -1518,9 +1518,9 @@ def hashwrap(v):
 				w_d[name_hsh] = hashfunc
 			prefix = f'{name_w_l} = {name_writers}[{name_hsh}('
 			hix = self._order.index(hl)
-			f_____.append('%s%s) %% %d]' % (prefix, names[hix], slices,))
-			f_list.append('%sv[%d]) %% %d]' % (prefix, hix, slices,))
-			f_dict.append('%sd[%r]) %% %d]' % (prefix, hl, slices,))
+			f_____.append(f'{prefix}{names[hix]}) % {slices}]')
+			f_list.append(f'{prefix}v[{hix}]) % {slices}]')
+			f_dict.append(f'{prefix}d[{hl!r}]) % {slices}]')
 		else:
 			from itertools import cycle
 			w_d[name_cyc] = cycle(range(slices))
@@ -1529,9 +1529,9 @@ def hashwrap(v):
 			f_list.append(code)
 			f_dict.append(code)
 		for ix in range(len(names)):
-			f_____.append('%s[%d](%s)' % (name_w_l, ix, names[ix],))
-			f_list.append('%s[%d](v[%d])' % (name_w_l, ix, ix,))
-			f_dict.append('%s[%d](d[%r])' % (name_w_l, ix, self._order[ix],))
+			f_____.append(f'{name_w_l}[{ix}]({names[ix]})')
+			f_list.append(f'{name_w_l}[{ix}](v[{ix}])')
+			f_dict.append(f'{name_w_l}[{ix}](d[{self._order[ix]!r}])')
 		eval(compile('\n '.join(f_____), ''     , 'exec'), w_d)
 		eval(compile('\n '.join(f_list), '', 'exec'), w_d)
 		eval(compile('\n '.join(f_dict), '', 'exec'), w_d)
@@ -1549,7 +1549,7 @@ def _close(self, sliceno, writers):
 			w.close()
 		len_set = set(lens.values())
 		if len(len_set) != 1:
-			raise DatasetUsageError("Not all columns have the same linecount in slice %d: %r" % (sliceno, lens))
+			raise DatasetUsageError(f"Not all columns have the same linecount in slice {sliceno}: {lens!r}")
 		self._lens[sliceno] = len_set.pop()
 		self._minmax[sliceno] = minmax
 
@@ -1786,7 +1786,7 @@ def range_check_function(bottom, top, none_support=False, index=None):
 	and/or top to be None. Skips None values if none_support is true."""
 	if_l = []
 	d = {}
-	v_str = 'v' if index is None else 'v[%d]' % (index,)
+	v_str = 'v' if index is None else f'v[{index}]'
 	def add_if(op, v):
 		if if_l:
 			if_l.append(' and ')
diff --git a/accelerator/dsutil.py b/accelerator/dsutil.py
index 2d47316b..0b8ab162 100644
--- a/accelerator/dsutil.py
+++ b/accelerator/dsutil.py
@@ -217,7 +217,7 @@ def _sanity_check_float_hashing():
 	def check(typ, msg, want, *a):
 		for ix, v in enumerate(a):
 			if v != want:
-				raise _SanityError("%s did not hash %s value correctly. (%d)" % (typ, msg, ix,))
+				raise _SanityError(f"{typ} did not hash {msg} value correctly. ({ix})")
 
 	# Test that the float types (including number) hash floats the same,
 	# and that float32 rounds as expected.
diff --git a/accelerator/examples/a_example_writeslicedfile.py b/accelerator/examples/a_example_writeslicedfile.py
index 46b16fe6..8a936262 100644
--- a/accelerator/examples/a_example_writeslicedfile.py
+++ b/accelerator/examples/a_example_writeslicedfile.py
@@ -4,7 +4,7 @@
 def analysis(sliceno, job):
 	# save one file per analysis process...
 	filename = 'myfile1'
-	data = 'This is job %s analysis slice %d.' % (job, sliceno,)
+	data = f'This is job {job} analysis slice {sliceno}.'
 	job.save(data, filename, sliceno=sliceno)
 
 
diff --git a/accelerator/extras.py b/accelerator/extras.py
index 2a51e3cc..382a9342 100644
--- a/accelerator/extras.py
+++ b/accelerator/extras.py
@@ -45,7 +45,7 @@ def _fn(filename, jobid, sliceno):
 	elif jobid:
 		filename = Job(jobid).filename(filename, sliceno)
 	elif sliceno is not None:
-		filename = '%s.%d' % (filename, sliceno,)
+		filename = f'{filename}.{sliceno}'
 	return filename
 
 def _type_list_or(v, t, falseval, listtype):
@@ -186,7 +186,7 @@ def job_post(jobid):
 		d.files = sorted(fn[len(prefix):] if fn.startswith(prefix) else fn for fn in d.files)
 		version = 1
 	if version != 1:
-		raise AcceleratorError("Don't know how to load post.json version %d (in %s)" % (d.version, jobid,))
+		raise AcceleratorError(f"Don't know how to load post.json version {d.version} (in {jobid})")
 	return d
 
 def _pickle_save(variable, filename, temp, _hidden):
@@ -324,7 +324,7 @@ def __init__(self, filename, temp=None, _hidden=False):
 			# Normalise filename so it always contains the job path (unless already absolute)
 			filename = job.filename(filename)
 		self.filename = filename
-		self.tmp_filename = '%s.%dtmp' % (filename, os.getpid(),)
+		self.tmp_filename = f'{filename}.{os.getpid()}tmp'
 		self.temp = temp
 		self._hidden = _hidden
 
@@ -365,7 +365,7 @@ def __iter__(self):
 		return self
 	def _loader(self, ix, slices):
 		for sliceno in slices:
-			yield pickle_load("Analysis.%d." % (ix,), sliceno=sliceno)
+			yield pickle_load(f"Analysis.{ix}.", sliceno=sliceno)
 	def __next__(self):
 		if self._is_tupled:
 			return next(self._tupled)
@@ -441,13 +441,13 @@ def _merge_auto_single(self, it, ix):
 		to_check = data
 		while hasattr(to_check, "values"):
 			if not to_check:
-				raise self._exc("Empty value at depth %d (index %d)" % (depth, ix,))
+				raise self._exc(f"Empty value at depth {depth} (index {ix})")
 			to_check = first_value(to_check)
 			depth += 1
 		if hasattr(to_check, "update"): # like a set
 			depth += 1
 		if not depth:
-			raise self._exc("Top level has no .values (index %d)" % (ix,))
+			raise self._exc(f"Top level has no .values (index {ix})")
 		def upd(aggregate, part, level):
 			if level == depth:
 				aggregate.update(part)
diff --git a/accelerator/job.py b/accelerator/job.py
index 83beaf6d..a24996bb 100644
--- a/accelerator/job.py
+++ b/accelerator/job.py
@@ -105,7 +105,7 @@ def __new__(cls, jobid, method=None):
 
 	@classmethod
 	def _create(cls, name, number):
-		return Job('%s-%d' % (name, number,))
+		return Job(f'{name}-{number}')
 
 	@_cachedprop
 	def method(self):
@@ -141,7 +141,7 @@ def filename(self, filename, sliceno=None):
 		if isinstance(filename, Path):
 			filename = str(filename)
 		if sliceno is not None:
-			filename = '%s.%d' % (filename, sliceno,)
+			filename = f'{filename}.{sliceno}'
 		return os.path.join(self.path, filename)
 
 	def open(self, filename, mode='r', sliceno=None, encoding=None, errors=None):
diff --git a/accelerator/launch.py b/accelerator/launch.py
index afb7aa0d..3e42ea49 100644
--- a/accelerator/launch.py
+++ b/accelerator/launch.py
@@ -83,13 +83,13 @@ def call_analysis(analysis_func, sliceno_, delayed_start, q, preserve_result, pa
 		for fd in output_fds:
 			os.close(fd)
 		os.close(_prof_fd)
-		slicename = 'analysis(%d)' % (sliceno_,)
+		slicename = f'analysis({sliceno_})'
 		setproctitle(slicename)
 		from accelerator.extras import saved_files, _backgrounded_wait
 		saved_files.clear() # don't inherit (and then return) the files from prepare
 		if delayed_start:
 			os.close(delayed_start[1])
-			update = statmsg._start('waiting for concurrency limit (%d)' % (sliceno_,), parent_pid, True)
+			update = statmsg._start(f'waiting for concurrency limit ({sliceno_})', parent_pid, True)
 			if os.read(delayed_start[0], 1) != b'a':
 				raise AcceleratorError('bad delayed_start, giving up')
 			update(slicename)
@@ -139,7 +139,7 @@ def save(item, name):
 				if sliceno_ == 0:
 					blob.save(len(res), "Analysis.tuple", temp=True)
 				for ix, item in enumerate(res):
-					save(item, "Analysis.%d." % (ix,))
+					save(item, f"Analysis.{ix}.")
 			else:
 				if sliceno_ == 0:
 					blob.save(False, "Analysis.tuple", temp=True)
@@ -184,7 +184,7 @@ def fork_analysis(slices, concurrency, analysis_func, kw, preserve_result, outpu
 			# The rest will wait on this queue
 			delayed_start = os.pipe()
 			delayed_start_todo = slices - i
-		p = SimplifiedProcess(target=call_analysis, args=(analysis_func, i, delayed_start, q, preserve_result, pid, output_fds), kwargs=kw, name='analysis-%d' % (i,))
+		p = SimplifiedProcess(target=call_analysis, args=(analysis_func, i, delayed_start, q, preserve_result, pid, output_fds), kwargs=kw, name=f'analysis-{i}')
 		children.append(p)
 	for fd in output_fds:
 		os.close(fd)
@@ -206,7 +206,7 @@ def fork_analysis(slices, concurrency, analysis_func, kw, preserve_result, outpu
 				else:
 					exit_count -= 1
 					if p.exitcode:
-						raise AcceleratorError("%s terminated with exitcode %d" % (p.name, p.exitcode,))
+						raise AcceleratorError(f"{p.name} terminated with exitcode {p.exitcode}")
 			children = still_alive
 			reap_time = monotonic() + 5
 		# If a process dies badly we may never get a message here.
@@ -234,7 +234,7 @@ def fork_analysis(slices, concurrency, analysis_func, kw, preserve_result, outpu
 		if len(finishjob) != 1 and not s_tb:
 			s_tb = 'not all slices agreed about job.finish_early() in analysis'
 		if s_tb:
-			data = [{'analysis(%d)' % (s_no,): s_tb}, None]
+			data = [{f'analysis({s_no})': s_tb}, None]
 			writeall(_prof_fd, json.dumps(data).encode('utf-8'))
 			exitfunction()
 		if delayed_start_todo:
@@ -286,7 +286,7 @@ def fmt_tb(skip_level):
 			msg.append("  " * ix)
 			msg.append(txt)
 			if line_report and line_report[0]:
-				msg.append(' reached line %d' % (line_report[0].count,))
+				msg.append(f' reached line {line_report[0].count}')
 			msg.append("\n")
 	msg.extend(format_exception_only(e_type, e))
 	return ''.join(msg)
diff --git a/accelerator/methods.py b/accelerator/methods.py
index be49306c..571fe163 100644
--- a/accelerator/methods.py
+++ b/accelerator/methods.py
@@ -282,6 +282,6 @@ def read_methods_conf(dirname, autodiscover):
 			except IndexError:
 				version = 'DEFAULT'
 			if data:
-				raise AcceleratorError('Trailing garbage on %s:%d: %s' % (filename, lineno, line,))
+				raise AcceleratorError(f'Trailing garbage on {filename}:{lineno}: {line}')
 			db[method] = DotDict(version=version)
 	return db
diff --git a/accelerator/mp.py b/accelerator/mp.py
index e9f5467c..54477fde 100644
--- a/accelerator/mp.py
+++ b/accelerator/mp.py
@@ -30,7 +30,7 @@
 from accelerator.compat import QueueEmpty, monotonic, selectors
 
 
-assert select.PIPE_BUF >= 512, "POSIX says PIPE_BUF is at least 512, you have %d" % (select.PIPE_BUF,)
+assert select.PIPE_BUF >= 512, f"POSIX says PIPE_BUF is at least 512, you have {select.PIPE_BUF}"
 
 PIPE_BUF = min(select.PIPE_BUF, 65536)
 MAX_PART = PIPE_BUF - 6
@@ -245,7 +245,7 @@ def __init__(self, target, args=(), kwargs={}, name=None, stdin=None, ignore_EPI
 			os.kill(os.getpid(), signal.SIGINT)
 		except Exception as e:
 			if not isinstance(e, OSError) or e.errno != errno.EPIPE:
-				print("Exception in %d %r:" % (os.getpid(), name), file=sys.stderr)
+				print(f"Exception in {os.getpid()} {name!r}:", file=sys.stderr)
 				print_exc(file=sys.stderr)
 			elif ignore_EPIPE:
 				rc = 0
diff --git a/accelerator/runner.py b/accelerator/runner.py
index 5969ed80..2fd93b1f 100644
--- a/accelerator/runner.py
+++ b/accelerator/runner.py
@@ -402,7 +402,7 @@ def __init__(self, pid, sock, python):
 		self._lock = TLock()
 		self._thread = Thread(
 			target=self._receiver,
-			name="%d receiver" % (pid,),
+			name=f"{pid} receiver",
 		)
 		self._thread.daemon = True
 		self._thread.start()
@@ -554,9 +554,9 @@ def new_runners(config, used_versions):
 			pass
 	r1, r2 = resource.getrlimit(resource.RLIMIT_NOFILE)
 	if r1 < r2:
-		print("WARNING: Failed to raise RLIMIT_NOFILE to %d. Set to %d." % (r2, r1,))
+		print(f"WARNING: Failed to raise RLIMIT_NOFILE to {r2}. Set to {r1}.")
 	if r1 < 5000:
-		print("WARNING: RLIMIT_NOFILE is %d, that's not much." % (r1,))
+		print(f"WARNING: RLIMIT_NOFILE is {r1}, that's not much.")
 
 	wait_for = []
 	try:
diff --git a/accelerator/server.py b/accelerator/server.py
index 859f163c..6848807b 100644
--- a/accelerator/server.py
+++ b/accelerator/server.py
@@ -199,7 +199,7 @@ def _handle_req(self, path, args):
 					else:
 						direction, kind = 'forward', 'later'
 						available = len(jobs) - start_ix - 1
-					res = {'error': 'tried to go %d jobs %s from %s, but only %d %s %s %s jobs available' % (abs(num), direction, jobs[start_ix], available, kind, typ, method,)}
+					res = {'error': f'tried to go {abs(num)} jobs {direction} from {jobs[start_ix]}, but only {available} {kind} {typ} {method} jobs available'}
 			self.do_response(200, 'text/json', res)
 
 		elif path[0] == 'job_is_current':
@@ -354,7 +354,7 @@ def exitfunction(*a):
 		signal.signal(signal.SIGTERM, signal.SIG_IGN)
 		signal.signal(signal.SIGINT, signal.SIG_IGN)
 	print()
-	print('The deathening! %d %s' % (os.getpid(), children,))
+	print(f'The deathening! {os.getpid()} {children}')
 	print()
 	for child in list(children):
 		try:
@@ -509,14 +509,14 @@ def buf_up(fh, opt):
 	for n in ("project_directory", "result_directory", "input_directory",):
 		v = config.get(n)
 		n = n.replace("_", " ")
-		print("%17s: %s" % (n, v,))
+		print(f"{n:>17}: {v}")
 	for n in ("board", "urd",):
 		v = config.get(n + '_listen')
 		if v and not config.get(n + '_local', True):
 			extra = ' (remote)'
 		else:
 			extra = ''
-		print("%17s: %s%s" % (n, v, extra,))
+		print(f"{n:>17}: {v}{extra}")
 	print()
 
 	print(f"Serving on {config.listen}\n", file=sys.stderr)
diff --git a/accelerator/setupfile.py b/accelerator/setupfile.py
index 397a7636..26d5d491 100644
--- a/accelerator/setupfile.py
+++ b/accelerator/setupfile.py
@@ -79,7 +79,7 @@ def load_setup(jobid):
 		# no changes here, it's only used to know how to find datasets
 		version = 4
 	if version != 4:
-		raise AcceleratorError("Don't know how to load setup.json version %d (in %s)" % (d.version, jobid,))
+		raise AcceleratorError(f"Don't know how to load setup.json version {d.version} (in {jobid})")
 	return d
 
 def update_setup(jobid, **kw):
diff --git a/accelerator/shell/__init__.py b/accelerator/shell/__init__.py
index 82fe09cb..886cd4db 100644
--- a/accelerator/shell/__init__.py
+++ b/accelerator/shell/__init__.py
@@ -189,7 +189,7 @@ def cmd_abort(argv):
 	a = Automata(cfg.url)
 	res = a.abort()
 	if not args.quiet:
-		print("Killed %d running job%s." % (res.killed, '' if res.killed == 1 else 's'))
+		print(f"Killed {res.killed} running job{'' if res.killed == 1 else 's'}.")
 cmd_abort.help = '''abort running job(s)'''
 
 def cmd_alias(argv):
diff --git a/accelerator/shell/ds.py b/accelerator/shell/ds.py
index 3502d086..2164a047 100644
--- a/accelerator/shell/ds.py
+++ b/accelerator/shell/ds.py
@@ -194,7 +194,7 @@ def fmt_minmax(val):
 					return str(val)
 			minlen = max(len(fmt_minmax(chain.min(n))) for n in ds.columns)
 			maxlen = max(len(fmt_minmax(chain.max(n))) for n in ds.columns)
-			minmax_template = '[%%%ds, %%%ds]' % (min(18, minlen), min(18, maxlen),)
+			minmax_template = f'[%{min(18, minlen)}s, %{min(18, maxlen)}s]'
 			def prettyminmax(n):
 				minval, maxval = chain.min(n), chain.max(n)
 				if args.suppress_minmax or minval is None:
diff --git a/accelerator/shell/grep.py b/accelerator/shell/grep.py
index 2337733c..4faf2446 100644
--- a/accelerator/shell/grep.py
+++ b/accelerator/shell/grep.py
@@ -184,7 +184,7 @@ def __call__(self, parser, namespace, values, option_string=None):
 				except ValueError:
 					raise ArgumentError(self, f'invalid int value for {name}: {value!r}')
 				if value < min_value[name] or value > 9999:
-					raise ArgumentError(self, 'invalid value for %s: %d' % (name, value,))
+					raise ArgumentError(self, f'invalid value for {name}: {value}')
 				tab_length[name] = value
 			# -T overrides -t
 			namespace.separator = None
@@ -239,7 +239,7 @@ def __call__(self, parser, namespace, values, option_string=None):
 		     "TABLEN works like normal tabs\n" +
 		     "FIELDLEN sets a longer minimum between fields\n" +
 		     "MINLEN sets a minimum len for all separators\n" +
-		     "use \"-T/\" to just activate it (sets %d/%d/%d)" % (tab_length.tab_len, tab_length.field_len, tab_length.min_len,)
+		     f"use \"-T/\" to just activate it (sets {tab_length.tab_len}/{tab_length.field_len}/{tab_length.min_len})"
 	)
 	parser.add_argument('-B', '--before-context', type=int, default=0, metavar='NUM', help="print NUM lines of leading context", )
 	parser.add_argument('-A', '--after-context',  type=int, default=0, metavar='NUM', help="print NUM lines of trailing context", )
@@ -325,7 +325,7 @@ def __call__(self, parser, namespace, values, option_string=None):
 	if args.slice:
 		want_slices = []
 		for s in args.slice:
-			assert 0 <= s < g.slices, "Slice %d not available" % (s,)
+			assert 0 <= s < g.slices, f"Slice {s} not available"
 			if s not in want_slices:
 				want_slices.append(s)
 	else:
@@ -590,7 +590,7 @@ def show(sig, frame):
 						msg = f'{round(p * 100):d}% of {total_lines_per_slice_at_ds[-1][sliceno]:n} lines'
 						if show_ds:
 							msg = f'{msg} (in {datasets[ds_ix].quoted})'
-					msg = '%9d: %s' % (sliceno, msg,)
+					msg = f'{sliceno:9}: {msg}'
 					if p < bad_cutoff:
 						msg = colour(msg, 'grep/infohighlight')
 					else:
@@ -606,7 +606,7 @@ def show(sig, frame):
 					msg = f'{msg} (in {ds_name}{extra})'
 			worst = min(progress_fraction)
 			if worst < bad_cutoff:
-				msg = '%s, worst %d%%' % (msg, round(worst * 100),)
+				msg = f'{msg}, worst {round(worst * 100)}%'
 			msg = colour(f'  SUMMARY: {msg}', 'grep/info')
 			write(2, msg.encode('utf-8') + b'\n')
 		for signame in ('SIGINFO', 'SIGUSR1'):
@@ -1362,7 +1362,7 @@ def gen_headers(headers):
 		p = mp.SimplifiedProcess(
 			target=one_slice,
 			args=(sliceno, q_in, q_out, q_to_close,),
-			name='slice-%d' % (sliceno,),
+			name=f'slice-{sliceno}',
 			ignore_EPIPE=bool(liner),
 		)
 		children.append(p)
diff --git a/accelerator/shell/hist.py b/accelerator/shell/hist.py
index aaa83765..4a514109 100644
--- a/accelerator/shell/hist.py
+++ b/accelerator/shell/hist.py
@@ -295,7 +295,7 @@ def collect_hist(hist, part):
 		total_found = 0 # so we don't print about it later
 		if args.max_count:
 			if NaN in hist:
-				print(colour('WARNING: Ignored %d NaN values.' % (hist[NaN],), 'hist/warning'), file=sys.stderr)
+				print(colour(f'WARNING: Ignored {hist[NaN]} NaN values.', 'hist/warning'), file=sys.stderr)
 			hist[args.max_count - 1] += hist[args.max_count] # top value should not be in a separate bin
 			hist, fmt = formatter([(name, hist[ix]) for ix, name in enumerate(bin_names)])
 		else:
diff --git a/accelerator/shell/init.py b/accelerator/shell/init.py
index f14f7ffe..7d86b4ad 100644
--- a/accelerator/shell/init.py
+++ b/accelerator/shell/init.py
@@ -123,7 +123,7 @@ def free(port):
 	for port in ports:
 		if all(free(port + n) for n in range(count)):
 			return port
-	raise Exception('Failed to find %d consecutive free TCP ports on %s in range(%d, %d)' % (count, hostname, low, high))
+	raise Exception(f'Failed to find {count} consecutive free TCP ports on {hostname} in range({low}, {high})')
 
 
 def git(method_dir):
@@ -244,9 +244,9 @@ def add_argument(name, default=None, help='', **kw):
 		else:
 			port = find_free_ports(0x3000, 0x8000)
 		listen = DotDict(
-			server='%s:%d' % (host, port,),
-			board='%s:%d' % (host, port + 1,),
-			urd='%s:%d' % (host, port + 2,),
+			server=f'{host}:{port}',
+			board=f'{host}:{port + 1}',
+			urd=f'{host}:{port + 2}',
 		)
 
 	if options.slices is None:
@@ -320,7 +320,7 @@ def plausible_jobdir(n):
 			if exists(workdir):
 				workdir_slices = slice_count(workdir)
 				if workdir_slices not in (None, options.slices):
-					raise UserError('Workdir %r has %d slices, refusing to continue with %d slices' % (workdir, workdir_slices, options.slices,))
+					raise UserError(f'Workdir {workdir!r} has {workdir_slices} slices, refusing to continue with {options.slices} slices')
 		if exists(first_workdir_path) and any(map(plausible_jobdir, listdir(first_workdir_path))):
 			raise UserError(f'Workdir {first_workdir_path!r} already has jobs in it.')
 
@@ -338,7 +338,7 @@ def plausible_jobdir(n):
 			makedirs(path)
 		if options.force or not exists(slices_conf(path)):
 			with open(slices_conf(path), 'w') as fh:
-				fh.write('%d\n' % (options.slices,))
+				fh.write(f'{options.slices}\n')
 	method_dir = options.name
 	if not exists(method_dir):
 		makedirs(method_dir)
diff --git a/accelerator/shell/job.py b/accelerator/shell/job.py
index 1fa301bf..d9a8c886 100644
--- a/accelerator/shell/job.py
+++ b/accelerator/shell/job.py
@@ -81,7 +81,7 @@ def list_of_things(name, things):
 		for thing in things:
 			print('   ', thing)
 		if total > len(things):
-			print('    ... and %d more' % (total - len(things),))
+			print(f'    ... and {total - len(things)} more')
 	if job.datasets:
 		list_of_things('datasets', [ds.quoted for ds in job.datasets])
 	try:
@@ -116,7 +116,7 @@ def list_of_things(name, things):
 			print(job, 'produced no output')
 			print()
 	elif out:
-		print('%s produced %d bytes of output, use --output/-o to see it' % (job, sum(len(v) for v in out.values()),))
+		print(f'{job} produced {sum((len(v) for v in out.values()))} bytes of output, use --output/-o to see it')
 		print()
 
 def show_source(job, pattern='*'):
@@ -202,7 +202,7 @@ def show_output_d(d, verbose):
 				else:
 					print()
 				if isinstance(k, int):
-					k = 'analysis(%d)' % (k,)
+					k = f'analysis({k})'
 				print(colour(k, 'job/header'))
 				print(colour('=' * len(k), 'job/header'))
 			print(out, end='' if out.endswith('\n') else '\n')
diff --git a/accelerator/shell/parser.py b/accelerator/shell/parser.py
index 2b78ad98..c09c43fe 100644
--- a/accelerator/shell/parser.py
+++ b/accelerator/shell/parser.py
@@ -87,7 +87,7 @@ def job_up(job, count):
 			if prev:
 				prev = prev.job
 		if not prev:
-			raise JobNotFound('Tried to go %d up from %s, but only %d previous jobs available' % (count, err_job, ix,))
+			raise JobNotFound(f'Tried to go {count} up from {err_job}, but only {ix} previous jobs available')
 		job = prev
 	return job
 
@@ -191,7 +191,7 @@ def _name2job_do_tildes(cfg, job, current, tildes):
 			job = job_up(job, count)
 		elif char == '<':
 			if count > job.number:
-				raise JobNotFound('Tried to go %d jobs back from %s.' % (count, job,))
+				raise JobNotFound(f'Tried to go {count} jobs back from {job}.')
 			job = Job._create(job.workdir, job.number - count)
 		elif char == '>':
 			job = Job._create(job.workdir, job.number + count)
@@ -307,7 +307,7 @@ def follow(key, motion):
 			res = ds
 			for done in range(count):
 				if not getattr(res, key):
-					raise DatasetNotFound('Tried to go %d %s from %s, but only %d available (stopped on %s)' % (count, motion, ds, done, res,))
+					raise DatasetNotFound(f'Tried to go {count} {motion} from {ds}, but only {done} available (stopped on {res})')
 				res = getattr(res, key)
 			return res
 		for char, count in tildes:
@@ -318,7 +318,7 @@ def follow(key, motion):
 	slices = ds.job.params.slices
 	from accelerator import g
 	if hasattr(g, 'slices'):
-		assert g.slices == slices, "Dataset %s needs %d slices, by we are already using %d slices" % (ds, slices, g.slices)
+		assert g.slices == slices, f"Dataset {ds} needs {slices} slices, by we are already using {g.slices} slices"
 	else:
 		g.slices = slices
 	return ds
diff --git a/accelerator/standard_methods/a_csvexport.py b/accelerator/standard_methods/a_csvexport.py
index 1b7a890d..a68dafca 100644
--- a/accelerator/standard_methods/a_csvexport.py
+++ b/accelerator/standard_methods/a_csvexport.py
@@ -195,7 +195,7 @@ def analysis(sliceno, job):
 		if '%' in options.filename:
 			filename = options.filename % (sliceno,)
 		else:
-			filename = '%s.%d' % (options.filename, sliceno,)
+			filename = f'{options.filename}.{sliceno}'
 		csvexport(sliceno, filename, options.labelsonfirstline)
 		job.register_file(filename)
 	else:
@@ -205,7 +205,7 @@ def analysis(sliceno, job):
 def synthesis(job, slices):
 	if not options.sliced:
 		def msg(sliceno):
-			return "Assembling %s (%d/%d)" % (options.filename, sliceno + 1, slices,)
+			return f"Assembling {options.filename} ({sliceno + 1}/{slices})"
 		with status(msg(0)) as update:
 			with job.open(options.filename, "wb") as outfh:
 				for sliceno in range(slices):
diff --git a/accelerator/standard_methods/a_csvimport.py b/accelerator/standard_methods/a_csvimport.py
index 64d27fd0..b67e75ed 100644
--- a/accelerator/standard_methods/a_csvimport.py
+++ b/accelerator/standard_methods/a_csvimport.py
@@ -133,7 +133,7 @@ def char2int(name, empty_value, specials="empty"):
 	return cstuff.backend.char2int(char)
 
 def import_slice(fallback_msg, fd, sliceno, slices, field_count, out_fns, gzip_mode, separator, r_num, quote_char, lf_char, allow_bad, allow_extra_empty):
-	fn = "import.success.%d" % (sliceno,)
+	fn = f"import.success.{sliceno}"
 	fh = open(fn, "wb+")
 	real_stderr = os.dup(2)
 	try:
@@ -310,7 +310,7 @@ def analysis(sliceno, slices, prepare_res, update_top_status):
 	r_num = cstuff.mk_uint64(9) # [good_count, bad_count, comment_count, good_min,max, bad_min,max, comment_min,max]
 	gzip_mode = b"wb%d" % (options.compression,)
 	try:
-		import_slice("c backend failed in slice %d" % (sliceno,), fds[sliceno], sliceno, slices, len(labels), out_fns, gzip_mode, separator, r_num, quote_char, lf_char, options.allow_bad, options.allow_extra_empty)
+		import_slice(f"c backend failed in slice {sliceno}", fds[sliceno], sliceno, slices, len(labels), out_fns, gzip_mode, separator, r_num, quote_char, lf_char, options.allow_bad, options.allow_extra_empty)
 	finally:
 		os.close(fds[sliceno])
 	return list(r_num)
diff --git a/accelerator/standard_methods/a_csvimport_zip.py b/accelerator/standard_methods/a_csvimport_zip.py
index 31cbc9eb..ee3cb5c4 100644
--- a/accelerator/standard_methods/a_csvimport_zip.py
+++ b/accelerator/standard_methods/a_csvimport_zip.py
@@ -147,7 +147,7 @@ def step(self, msg):
 		self.z_so_far += self.z[self.cnt_so_far]
 		self.cnt_so_far += 1
 		percent = self.z_so_far / self.z_total * 100
-		return '%s %s (file %d/%d, up to %d%% of total size)' % (msg, fn, self.cnt_so_far, self.cnt_total, percent,)
+		return f'{msg} {fn} (file {self.cnt_so_far}/{self.cnt_total}, up to {percent}% of total size)'
 
 def analysis(sliceno, slices, prepare_res, job):
 	lst = prepare_res[sliceno::slices]
diff --git a/accelerator/standard_methods/a_dataset_hashpart.py b/accelerator/standard_methods/a_dataset_hashpart.py
index 23418226..8654b674 100644
--- a/accelerator/standard_methods/a_dataset_hashpart.py
+++ b/accelerator/standard_methods/a_dataset_hashpart.py
@@ -55,9 +55,9 @@ def prepare_one(ix, source, previous, job, chain, slices):
 		if sliceno == slices - 1 and options.chain_slices and ix == len(chain) - 1:
 			name = "default"
 		else:
-			name = '%d.%d' % (ix, sliceno,)
+			name = f'{ix}.{sliceno}'
 		dw = job.datasetwriter(
-			caption="%s (slice %d)" % (caption, sliceno),
+			caption=f"{caption} (slice {sliceno})",
 			hashlabel=options.hashlabel,
 			filename=filename,
 			previous=previous,
diff --git a/accelerator/standard_methods/a_dataset_sort.py b/accelerator/standard_methods/a_dataset_sort.py
index fe4febf5..441c9e7e 100644
--- a/accelerator/standard_methods/a_dataset_sort.py
+++ b/accelerator/standard_methods/a_dataset_sort.py
@@ -208,7 +208,7 @@ def analysis(sliceno, params, prepare_res):
 		sort_idx, _ = sort(partial(ds_list.iterate, sliceno))
 		columniter = partial(ds_list.iterate, sliceno, copy_mode=True)
 	for ix, column in enumerate(datasets.source.columns, 1):
-		colstat = '%r (%d/%d)' % (column, ix, len(datasets.source.columns),)
+		colstat = f'{column!r} ({ix}/{len(datasets.source.columns)})'
 		with status('Reading ' + colstat):
 			lst = list(columniter(column))
 		with status('Writing ' + colstat):
diff --git a/accelerator/standard_methods/a_dataset_type.py b/accelerator/standard_methods/a_dataset_type.py
index bb381252..d693f6bc 100644
--- a/accelerator/standard_methods/a_dataset_type.py
+++ b/accelerator/standard_methods/a_dataset_type.py
@@ -143,13 +143,13 @@ def prepare_one(ix, source, chain, job, slices, previous_res):
 		# renamed over don't need to be duplicated
 		just_rename[k] = dup_rename.pop(k)
 	if dup_rename:
-		dup_ds = source.link_to_here(name='dup.%d' % (ix,), rename=dup_rename, column_filter=dup_rename.values())
+		dup_ds = source.link_to_here(name=f'dup.{ix}', rename=dup_rename, column_filter=dup_rename.values())
 		if source.hashlabel in dup_rename:
 			just_rename[source.hashlabel] = None
 	if just_rename:
-		source = source.link_to_here(name='rename.%d' % (ix,), rename=just_rename)
+		source = source.link_to_here(name=f'rename.{ix}', rename=just_rename)
 	if dup_rename:
-		source = source.merge(dup_ds, name='merge.%d' % (ix,))
+		source = source.merge(dup_ds, name=f'merge.{ix}')
 	none_support = set()
 	for colname, coltype in column2type.items():
 		if colname not in source.columns:
@@ -208,10 +208,10 @@ def prepare_one(ix, source, chain, job, slices, previous_res):
 				name = ds_name
 			else:
 				# This ds is either an earlier part of the chain or will be merged into ds_name in synthesis
-				name = '%s.%d' % (ds_name, sliceno,)
+				name = f'{ds_name}.{sliceno}'
 			dw = job.datasetwriter(
 				columns=columns,
-				caption='%s (from %s slice %d)' % (options.caption, source_name, sliceno,),
+				caption=f'{options.caption} (from {source_name} slice {sliceno})',
 				hashlabel=hashlabel,
 				filename=filename,
 				previous=previous,
@@ -289,7 +289,7 @@ def analysis(sliceno, slices, prepare_res):
 		dataset_type.numeric_comma = True
 	res = [analysis_one(sliceno, slices, p) for p in prepare_res]
 	for fn in ('slicemap', 'badmap',):
-		fn = '%s%d' % (fn, sliceno,)
+		fn = f'{fn}{sliceno}'
 		if exists(fn):
 			unlink(fn)
 	return res
@@ -327,7 +327,7 @@ def analysis_one(sliceno, slices, prepare_res):
 		column2type=column2type,
 	)
 	if options.filter_bad:
-		vars.badmap_fd = map_init(vars, 'badmap%d' % (sliceno,))
+		vars.badmap_fd = map_init(vars, f'badmap{sliceno}')
 		bad_count, default_count, minmax = analysis_lap(vars)
 		if sum(sum(c) for c in itervalues(bad_count)):
 			vars.first_lap = False
@@ -378,14 +378,14 @@ def it():
 def analysis_lap(vars):
 	if vars.rehashing:
 		if vars.first_lap:
-			out_fn = 'hashtmp.%d' % (vars.sliceno,)
+			out_fn = f'hashtmp.{vars.sliceno}'
 			colname = vars.dw.hashlabel
 			coltype = vars.column2type[colname]
 			vars.rehashing = False
 			real_coltype = one_column(vars, colname, coltype, [out_fn], True)
 			vars.rehashing = True
 			assert vars.res_bad_count[colname] == [0] # implicitly has a default
-			vars.slicemap_fd = map_init(vars, 'slicemap%d' % (vars.sliceno,), 'slicemap_size')
+			vars.slicemap_fd = map_init(vars, f'slicemap{vars.sliceno}', 'slicemap_size')
 			slicemap = mmap(vars.slicemap_fd, vars.slicemap_size)
 			vars.map_fhs.append(slicemap)
 			slicemap = Int16BytesWrapper(slicemap)
@@ -420,7 +420,7 @@ def one_column(vars, colname, coltype, out_fns, for_hasher=False):
 	else:
 		record_bad = 0
 		skip_bad = options.filter_bad
-	minmax_fn = 'minmax%d' % (vars.sliceno,)
+	minmax_fn = f'minmax{vars.sliceno}'
 
 	if coltype.split(':')[0].endswith('+None'):
 		coltype = ''.join(coltype.split('+None', 1))
@@ -468,7 +468,7 @@ def one_column(vars, colname, coltype, out_fns, for_hasher=False):
 	if not is_null_converter:
 		assert d.columns[colname].type in byteslike_types, f'{colname} has bad type in {d.quoted}'
 	in_fns.append(d.column_filename(colname, vars.sliceno))
-	in_msgnames.append('%s column %s slice %d' % (d.quoted, quote(colname), vars.sliceno,))
+	in_msgnames.append(f'{d.quoted} column {quote(colname)} slice {vars.sliceno}')
 	if d.columns[colname].offsets:
 		offsets.append(d.columns[colname].offsets[vars.sliceno])
 		max_counts.append(d.lines[vars.sliceno])
@@ -496,7 +496,7 @@ def one_column(vars, colname, coltype, out_fns, for_hasher=False):
 			c_slices = 1
 		bad_count = cstuff.mk_uint64(c_slices)
 		default_count = cstuff.mk_uint64(c_slices)
-		gzip_mode = "wb%d" % (options.compression,)
+		gzip_mode = f"wb{options.compression}"
 		if in_fns:
 			assert len(out_fns) == c_slices + vars.save_bad
 			res = c(*cstuff.bytesargs(in_fns, in_msgnames, len(in_fns), out_fns, gzip_mode, minmax_fn, default_value, default_len, default_value_is_None, empty_types_as_None, fmt, fmt_b, record_bad, skip_bad, vars.badmap_fd, vars.badmap_size, vars.save_bad, c_slices, vars.slicemap_fd, vars.slicemap_size, bad_count, default_count, offsets, max_counts))
@@ -626,7 +626,7 @@ def print(msg=''):
 			for colname in columns:
 				cnt = sum(sum(data[0].get(colname, ())) for data in analysis_res)
 				if cnt:
-					print('%14d   %s' % (cnt, colname,))
+					print(f'{cnt:14}   {colname}')
 		for s, cnt in enumerate(bad_line_count_per_slice):
 			dw_bad.set_lines(s, cnt)
 		dw_bad.set_compressions('gzip')
@@ -641,10 +641,10 @@ def print(msg=''):
 				slicecnt = 0
 				for sliceno, cnt in enumerate(defaulted):
 					if cnt:
-						print('        %5d   %d' % (sliceno, cnt,))
+						print(f'        {sliceno:5}   {cnt}')
 						slicecnt += 1
 				if slicecnt > 1:
-					print('        total   %d' % (sum(defaulted),))
+					print(f'        total   {sum(defaulted)}')
 	if dws: # rehashing
 		if dw: # not as a chain
 			final_bad_count = [data[1] for data in analysis_res]
diff --git a/accelerator/standard_methods/dataset_type.py b/accelerator/standard_methods/dataset_type.py
index 557dee02..3670780b 100644
--- a/accelerator/standard_methods/dataset_type.py
+++ b/accelerator/standard_methods/dataset_type.py
@@ -1449,7 +1449,7 @@ def _test():
 	protos.append(proto + ';')
 	funcs.append(code)
 
-copy_types = {typerename.get(k.split(':')[0], k.split(':')[0]): 'null_%d' % (v.size,) if v.size else 'null_blob' for k, v in convfuncs.items()}
+copy_types = {typerename.get(k.split(':')[0], k.split(':')[0]): f'null_{v.size}' if v.size else 'null_blob' for k, v in convfuncs.items()}
 copy_types['number'] = 'null_number'
 copy_types['pickle'] = 'null_blob'
 
diff --git a/accelerator/statmsg.py b/accelerator/statmsg.py
index 6e376ec3..1332ebb1 100644
--- a/accelerator/statmsg.py
+++ b/accelerator/statmsg.py
@@ -126,7 +126,7 @@ def _start(msg, parent_pid, is_analysis=False):
 		analysis_cookie = str(_cookie)
 	else:
 		analysis_cookie = ''
-	_send('start', '%d\0%s\0%s\0%f' % (parent_pid, analysis_cookie, msg, monotonic(),))
+	_send('start', f'{parent_pid}\x00{analysis_cookie}\x00{msg}\x00{monotonic():f}')
 	def update(msg):
 		_send('update', f'{msg}\x00\x00{analysis_cookie}')
 	return update
@@ -174,12 +174,12 @@ def print_status_stacks(stacks=None):
 	report_t = monotonic()
 	for pid, indent, msg, t in stacks:
 		if indent < 0:
-			print("%6d TAIL OF OUTPUT: (%.1f seconds ago)" % (pid, report_t - t,))
+			print(f"{pid:6} TAIL OF OUTPUT: ({report_t - t:.1f} seconds ago)")
 			msgs = list(filter(None, msg.split('\n')))[-3:]
 			for msg in msgs:
 				print("       " + colour.green(msg))
 		else:
-			print("%6d STATUS: %s%s (%.1f seconds)" % (pid, "    " * indent, msg, report_t - t))
+			print(f"{pid:6} STATUS: {'    ' * indent}{msg} ({report_t - t:.1f} seconds)")
 
 
 def _find(pid, cookie):
@@ -209,7 +209,7 @@ def statmsg_sink(sock):
 					if ix == len(stack) - 1:
 						stack.pop()
 					else:
-						print('POP OF WRONG STATUS: %d:%s (index %s of %d)' % (pid, msg, ix, len(stack)))
+						print(f'POP OF WRONG STATUS: {pid}:{msg} (index {ix} of {len(stack)})')
 						wrong_pops += 1
 						if wrong_pops == 3:
 							print('Getting a lot of these? Are you interleaving dataset iterators? Set status_reporting=False on all but one.')
@@ -218,7 +218,7 @@ def statmsg_sink(sock):
 					msg, _, cookie = msg.split('\0', 3)
 					stack, ix = _find(pid, cookie)
 					if ix is None:
-						print('UPDATE TO UNKNOWN STATUS %d:%s: %s' % (pid, cookie, msg))
+						print(f'UPDATE TO UNKNOWN STATUS {pid}:{cookie}: {msg}')
 					else:
 						stack[ix] = (msg, stack[ix][1], cookie)
 				elif typ == 'output':
@@ -278,7 +278,7 @@ def _send(typ, message, pid=None):
 	if not _send_sock:
 		fd = int(os.getenv('BD_STATUS_FD'))
 		_send_sock = socket.fromfd(fd, socket.AF_UNIX, socket.SOCK_DGRAM)
-	header = ('%s\0%d\0' % (typ, pid or os.getpid(),)).encode('utf-8')
+	header = f'{typ}\x00{pid or os.getpid()}\x00'.encode('utf-8')
 	message = message.encode('utf-8')
 	if len(message) > 1450:
 		message = message[:300] + b'\n....\n' + message[-1100:]
@@ -293,5 +293,5 @@ def _send(typ, message, pid=None):
 			if e.errno == ENOTCONN:
 				# The server is dead, no use retrying.
 				return
-			print('Failed to send statmsg (type %s, try %d): %s' % (typ, ix, e))
+			print(f'Failed to send statmsg (type {typ}, try {ix}): {e}')
 			sleep(0.1 + ix)
diff --git a/accelerator/test_methods/a_test_compare_datasets.py b/accelerator/test_methods/a_test_compare_datasets.py
index 70cea8e8..6296c791 100644
--- a/accelerator/test_methods/a_test_compare_datasets.py
+++ b/accelerator/test_methods/a_test_compare_datasets.py
@@ -30,11 +30,11 @@ def analysis(sliceno):
 		except StopIteration:
 			try:
 				next(iter_b)
-				raise Exception("dataset b is longer than a in slice %d" % (sliceno,))
+				raise Exception(f"dataset b is longer than a in slice {sliceno}")
 			except StopIteration:
 				break
 		try:
 			b = next(iter_b)
 		except StopIteration:
-			raise Exception("dataset a is longer than b in slice %d" % (sliceno,))
+			raise Exception(f"dataset a is longer than b in slice {sliceno}")
 		assert a == b
diff --git a/accelerator/test_methods/a_test_csvimport_corner_cases.py b/accelerator/test_methods/a_test_csvimport_corner_cases.py
index ff05c0a9..7573b717 100644
--- a/accelerator/test_methods/a_test_csvimport_corner_cases.py
+++ b/accelerator/test_methods/a_test_csvimport_corner_cases.py
@@ -77,8 +77,8 @@ def verify_ds(options, d, d_bad, d_skipped, filename, d_columns=None):
 	if options.get("allow_bad"):
 		bad_ds = Dataset(jid, "bad")
 		for ix, data in bad_ds.iterate(None, ["lineno", "data"]):
-			assert ix in d_bad, "Bad bad_lineno %d in %r (%s/bad) %r" % (ix, filename, jid, data,)
-			assert data == d_bad[ix], "Wrong saved bad line %d in %r (%s/bad).\nWanted %r.\nGot    %r." % (ix, filename, jid, d_bad[ix], data,)
+			assert ix in d_bad, f"Bad bad_lineno {ix} in {filename!r} ({jid}/bad) {data!r}"
+			assert data == d_bad[ix], f"Wrong saved bad line {ix} in {filename!r} ({jid}/bad).\nWanted {d_bad[ix]!r}.\nGot    {data!r}."
 			del d_bad[ix]
 		verify_minmax(bad_ds, "lineno")
 	assert not d_bad, f"Not all bad lines returned from {filename!r} ({jid}), {set(d_bad.keys())!r} missing"
@@ -86,8 +86,8 @@ def verify_ds(options, d, d_bad, d_skipped, filename, d_columns=None):
 	if options.get("comment") or options.get("skip_lines"):
 		skipped_ds = Dataset(jid, "skipped")
 		for ix, data in skipped_ds.iterate(None, ["lineno", "data"]):
-			assert ix in d_skipped, "Bad skipped_lineno %d in %r (%s/skipped) %r" % (ix, filename, jid, data,)
-			assert data == d_skipped[ix], "Wrong saved skipped line %d in %r (%s/skipped).\nWanted %r.\nGot    %r." % (ix, filename, jid, d_skipped[ix], data,)
+			assert ix in d_skipped, f"Bad skipped_lineno {ix} in {filename!r} ({jid}/skipped) {data!r}"
+			assert data == d_skipped[ix], f"Wrong saved skipped line {ix} in {filename!r} ({jid}/skipped).\nWanted {d_skipped[ix]!r}.\nGot    {data!r}."
 			del d_skipped[ix]
 		verify_minmax(skipped_ds, "lineno")
 	assert not d_skipped, f"Not all bad lines returned from {filename!r} ({jid}), {set(d_skipped.keys())!r} missing"
diff --git a/accelerator/test_methods/a_test_csvimport_separators.py b/accelerator/test_methods/a_test_csvimport_separators.py
index b1a1a29d..3ba20ccb 100644
--- a/accelerator/test_methods/a_test_csvimport_separators.py
+++ b/accelerator/test_methods/a_test_csvimport_separators.py
@@ -68,14 +68,14 @@ def check_one(job, newline, sep, data, want_res=None, prefix="", quotes=False, l
 			newline='' if "\n" in newline else newline,
 		))
 	except JobError as e:
-		raise CSVImportException("Failed to csvimport for separator %d with newline %r, csvimport error was:\n%s" % (sep, newline, e.format_msg()))
+		raise CSVImportException(f"Failed to csvimport for separator {sep} with newline {newline!r}, csvimport error was:\n{e.format_msg()}")
 	ds = Dataset(jid)
 	labels = sorted(ds.columns)
 	if labels != data[0]:
-		raise WrongLabelsException("csvimport gave wrong labels for separator %d with newline %r: %r (expected %r)" % (sep, newline, labels, data[0],))
+		raise WrongLabelsException(f"csvimport gave wrong labels for separator {sep} with newline {newline!r}: {labels!r} (expected {data[0]!r})")
 	res = list(ds.iterate(None, data[0]))
 	if res != want_res:
-		raise WrongDataException("csvimport gave wrong data for separator %d with newline %r: %r (expected %r)" % (sep, newline, res, want_res,))
+		raise WrongDataException(f"csvimport gave wrong data for separator {sep} with newline {newline!r}: {res!r} (expected {want_res!r})")
 
 def synthesis(job):
 	# Any iso-8859-1 character is a valid separator, but let's try
diff --git a/accelerator/test_methods/a_test_csvimport_slicing.py b/accelerator/test_methods/a_test_csvimport_slicing.py
index ddfb4485..75dabe92 100644
--- a/accelerator/test_methods/a_test_csvimport_slicing.py
+++ b/accelerator/test_methods/a_test_csvimport_slicing.py
@@ -51,8 +51,8 @@ def add_comment(line):
 				if sometimes and randint(0, 9) == 3:
 					add_comment(sometimes % (ix, sliceno,))
 				if comments and sliceno % comments == 0:
-					add_comment('# line %d, before %d,%d' % (lineno[0], ix, sliceno,))
-				fh.write('%d,%d\n' % (ix, sliceno,))
+					add_comment(f'# line {lineno[0]}, before {ix},{sliceno}')
+				fh.write(f'{ix},{sliceno}\n')
 				want_linenos[sliceno].append(lineno[0])
 				lineno[0] += 1
 	job = subjobs.build(
@@ -67,16 +67,16 @@ def add_comment(line):
 	ds = job.dataset()
 	for sliceno in range(job.params.slices):
 		got = [int(x) for x in ds.iterate(sliceno, 'sliceno')]
-		assert got == [sliceno] * 10, "Slice %d has wrong slices in %s: %r" % (sliceno, ds.quoted, got,)
+		assert got == [sliceno] * 10, f"Slice {sliceno} has wrong slices in {ds.quoted}: {got!r}"
 		got = [int(x) for x in ds.iterate(sliceno, 'ix')]
-		assert got == list(range(10)), "Slice %d has wrong ixes in %s: %r" % (sliceno, ds.quoted, got,)
+		assert got == list(range(10)), f"Slice {sliceno} has wrong ixes in {ds.quoted}: {got!r}"
 		got = list(ds.iterate(sliceno, 'lineno'))
-		assert got == want_linenos[sliceno], "Slice %d has wrong lines in %s:\n    wanted %r\n    got    %r" % (sliceno, ds.quoted, want_linenos[sliceno], got,)
+		assert got == want_linenos[sliceno], f"Slice {sliceno} has wrong lines in {ds.quoted}:\n    wanted {want_linenos[sliceno]!r}\n    got    {got!r}"
 	if comments or sometimes or initial_skipped:
 		ds = job.dataset('skipped')
 		for sliceno in range(job.params.slices):
 			got = list(ds.iterate(sliceno, ('lineno', 'data')))
-			assert got == want_comments[sliceno], "Slice %d has wrong skipped lines in %s:\n    wanted %r\n    got    %r" % (sliceno, ds.quoted, want_comments[sliceno], got,)
+			assert got == want_comments[sliceno], f"Slice {sliceno} has wrong skipped lines in {ds.quoted}:\n    wanted {want_comments[sliceno]!r}\n    got    {got!r}"
 
 
 def synthesis(job):
diff --git a/accelerator/test_methods/a_test_dataset_checksum.py b/accelerator/test_methods/a_test_dataset_checksum.py
index 6b849048..c0e2d29a 100644
--- a/accelerator/test_methods/a_test_dataset_checksum.py
+++ b/accelerator/test_methods/a_test_dataset_checksum.py
@@ -46,7 +46,7 @@ def prepare():
 	# z so it sorts last
 	columns['zpickle'] = 'pickle'
 	for ix, v in enumerate(test_data):
-		test_data[ix] = v + ([ix, 'line %d' % (ix,), {'line': ix}, 42],)
+		test_data[ix] = v + ([ix, f'line {ix}', {'line': ix}, 42],)
 	test_data[-1][-1][-1] = float('-inf')
 	a = DatasetWriter(name="a", columns=columns)
 	b = DatasetWriter(name="b", columns=columns, previous=a)
diff --git a/accelerator/test_methods/a_test_dataset_column_names.py b/accelerator/test_methods/a_test_dataset_column_names.py
index 96dbe488..afde6eac 100644
--- a/accelerator/test_methods/a_test_dataset_column_names.py
+++ b/accelerator/test_methods/a_test_dataset_column_names.py
@@ -36,14 +36,14 @@ def prepare():
 	return mk_dw("internal_names_analysis", internal_names_analysis)
 
 def analysis(sliceno, prepare_res):
-	prepare_res.write(*['a %d' % (sliceno,)] * 5)
-	prepare_res.write_list(['b %d' % (sliceno,)] * 5)
-	prepare_res.write_dict(dict(zip(internal_names_analysis, ['c %d' % (sliceno,)] * 5)))
+	prepare_res.write(*[f'a {sliceno}'] * 5)
+	prepare_res.write_list([f'b {sliceno}'] * 5)
+	prepare_res.write_dict(dict(zip(internal_names_analysis, [f'c {sliceno}'] * 5)))
 
 def synthesis(prepare_res, slices):
 	ds = prepare_res.finish()
 	for sliceno in range(slices):
-		assert list(ds.iterate(sliceno, internal_names_analysis)) == [('a %d' % (sliceno,),) * 5, ('b %d' % (sliceno,),) *5, ('c %d' % (sliceno,),) *5]
+		assert list(ds.iterate(sliceno, internal_names_analysis)) == [(f'a {sliceno}',) * 5, (f'b {sliceno}',) *5, (f'c {sliceno}',) *5]
 
 	in_parent = [ # list because order matters
 		"-",      # becomes _ because everything must be a valid python identifier.
diff --git a/accelerator/test_methods/a_test_dataset_concat.py b/accelerator/test_methods/a_test_dataset_concat.py
index 3dcd53a1..45732dac 100644
--- a/accelerator/test_methods/a_test_dataset_concat.py
+++ b/accelerator/test_methods/a_test_dataset_concat.py
@@ -52,7 +52,7 @@ def synthesis(job):
 
 	def data(ix):
 		d = {
-			'a': '%d' % (ix,),
+			'a': f'{ix}',
 			'b': bool(ix % 2),
 			'c': b'%d' % (ix,),
 			'd': complex(0, ix),
@@ -67,7 +67,7 @@ def data(ix):
 			'm': -1.0 / (ix + 1),
 			'n': {ix},
 			'o': time(0, ix // 60 % 60, ix % 60),
-			'p': u'%d' % (ix,),
+			'p': f'{ix}',
 			'extra': 0,
 		}
 		return {k: v for k, v in d.items() if k in types}
diff --git a/accelerator/test_methods/a_test_dataset_fanout.py b/accelerator/test_methods/a_test_dataset_fanout.py
index 3b21b9f9..7bc7a319 100644
--- a/accelerator/test_methods/a_test_dataset_fanout.py
+++ b/accelerator/test_methods/a_test_dataset_fanout.py
@@ -182,7 +182,7 @@ def chk(job, colnames, types, ds2lines, previous={}, hashlabel=None):
 		data = [('data',) + (ix + 1000,) * 4 + (str(ix),)]
 		want_data.append(data[0][1:])
 		all_types.append(
-			mk('all types %d' % (ix,), types, data, previous=previous)
+			mk(f'all types {ix}', types, data, previous=previous)
 		)
 		previous = all_types[-1]
 
diff --git a/accelerator/test_methods/a_test_dataset_parsing_writer.py b/accelerator/test_methods/a_test_dataset_parsing_writer.py
index d50be8ad..4c47be83 100644
--- a/accelerator/test_methods/a_test_dataset_parsing_writer.py
+++ b/accelerator/test_methods/a_test_dataset_parsing_writer.py
@@ -60,7 +60,7 @@ def test(typ, write_values, want_values, bad_values=[]):
 		for sliceno in range(slices):
 			want_slice = hashfilter(typ, want_values, sliceno)
 			got_slice = list(ds.iterate(sliceno, 'value'))
-			assert nanfix(got_slice) == nanfix(want_slice), "%s got %r, wanted %r in slice %d" % (typ, got_slice, want_slice, sliceno)
+			assert nanfix(got_slice) == nanfix(want_slice), f"{typ} got {got_slice!r}, wanted {want_slice!r} in slice {sliceno}"
 
 	inf = float('inf')
 	nan = float('nan')
diff --git a/accelerator/test_methods/a_test_dataset_rename_columns.py b/accelerator/test_methods/a_test_dataset_rename_columns.py
index cd544af1..0e0ffa5b 100644
--- a/accelerator/test_methods/a_test_dataset_rename_columns.py
+++ b/accelerator/test_methods/a_test_dataset_rename_columns.py
@@ -41,7 +41,7 @@ def synthesis(job):
 	dw = job.datasetwriter(name='b', hashlabel='b', columns=columns, previous=a)
 	dw.get_split_write()(1, 2, 3)
 	b = dw.finish()
-	names = ('link%d' % (ix,) for ix in range(1000)) # more than enough
+	names = (f'link{ix}' for ix in range(1000)) # more than enough
 	def chk(ds, want_hashlabel, want_previous, want_coltypes, rename):
 		got_job = subjobs.build('dataset_rename_columns', rename=rename, source=ds)
 		chk_inner(got_job.dataset(), want_hashlabel, want_previous, want_coltypes)
diff --git a/accelerator/test_methods/a_test_dataset_type_chaining.py b/accelerator/test_methods/a_test_dataset_type_chaining.py
index 03ac05ee..d5166435 100644
--- a/accelerator/test_methods/a_test_dataset_type_chaining.py
+++ b/accelerator/test_methods/a_test_dataset_type_chaining.py
@@ -34,7 +34,7 @@ def verify(a, b):
 			for sliceno in range(slices):
 				a_data = list(Dataset.iterate_list(sliceno, col, a))
 				b_data = list(map(str, Dataset.iterate_list(sliceno, col, b)))
-				assert a_data == b_data, '%r has different contents to %r in slice %d column %s' % (a, b, sliceno, col,)
+				assert a_data == b_data, f'{a!r} has different contents to {b!r} in slice {sliceno} column {col}'
 	def verify_sorted(a, b):
 		for col in 'abcd':
 			a_data = list(Dataset.iterate_list(None, col, a))
@@ -51,7 +51,7 @@ def write(name, previous, low, high, filter=lambda ix: True):
 		w = dw.get_split_write()
 		for ix in range(low, high):
 			if filter(ix):
-				w('%d' % (ix,), '%d.2' % (ix,), '%d%s' % (ix, '.5' if ix % 2 else ''), '[%d]' % (ix,))
+				w(f'{ix}', f'{ix}.2', f"{ix}{'.5' if ix % 2 else ''}", f'[{ix}]')
 		return dw.finish()
 	untyped_A = write('A', None, 0, 100)
 	untyped_B = write('B', untyped_A, 100, 1000)
diff --git a/accelerator/test_methods/a_test_dataset_type_corner_cases.py b/accelerator/test_methods/a_test_dataset_type_corner_cases.py
index eb8258f1..033d52e7 100644
--- a/accelerator/test_methods/a_test_dataset_type_corner_cases.py
+++ b/accelerator/test_methods/a_test_dataset_type_corner_cases.py
@@ -125,13 +125,13 @@ def test_numbers():
 		(16, (b'1b', b'0x1b', b'\r001b',),),
 		( 0, (b'27', b'\r033', b'0x1b',),),
 	):
-		types = ['%s_%d' % (typ, base,) for typ in ('int32', 'int64',)]
-		verify('base %d' % (base,), types, values, [27, 27, 27], all_source_types=all_source_types)
+		types = [f'{typ}_{base}' for typ in ('int32', 'int64',)]
+		verify(f'base {base}', types, values, [27, 27, 27], all_source_types=all_source_types)
 		types = [typ + 'i' for typ in types]
 		if base == 10:
 			types += ['float32i', 'float64i']
 		values = [v + b'garbage' for v in values]
-		verify('base %d i' % (base,), types, values, [27, 27, 27], all_source_types=all_source_types)
+		verify(f'base {base} i', types, values, [27, 27, 27], all_source_types=all_source_types)
 		all_source_types = False
 	verify('inty numbers', ['number', 'number:int'], [b'42', b'42.0', b'42.0000000', b'43.', b'.0'], [42, 42, 42, 43, 0], exact_types=True)
 	if options.numeric_comma:
diff --git a/accelerator/test_methods/a_test_dataset_type_hashing.py b/accelerator/test_methods/a_test_dataset_type_hashing.py
index 4528fb2a..eb914824 100644
--- a/accelerator/test_methods/a_test_dataset_type_hashing.py
+++ b/accelerator/test_methods/a_test_dataset_type_hashing.py
@@ -95,10 +95,10 @@ def synthesis(job, slices):
 	dw = job.datasetwriter(name='more types')
 	cols = {
 		'floatbooli': cycle(['1.42 or so', '0 maybe', '1 (exactly)']),
-		'datetime:%Y%m%d %H:%M': ['2019%02d%02d 17:%02d' % (t % 12 + 1, t % 28 + 1, t % 60) for t in range(1000)],
-		'date:%Y%m%d': ['2019%02d%02d' % (t % 12 + 1, t % 28 + 1,) for t in range(1000)],
-		'time:%H:%M': ['%02d:%02d' % (t // 60, t % 60) for t in range(1000)],
-		'timei:%H:%M': ['%02d:%02d%c' % (t // 60, t % 60, chr(t % 26 + 65)) for t in range(1000)],
+		'datetime:%Y%m%d %H:%M': [f'2019{t % 12 + 1:02}{t % 28 + 1:02} 17:{t % 60:02}' for t in range(1000)],
+		'date:%Y%m%d': [f'2019{t % 12 + 1:02}{t % 28 + 1:02}' for t in range(1000)],
+		'time:%H:%M': [f'{t // 60:02}:{t % 60:02}' for t in range(1000)],
+		'timei:%H:%M': [f'{t // 60:02}:{t % 60:02}{chr(t % 26 + 65)}' for t in range(1000)],
 	}
 	gens = []
 	for coltype, gen in cols.items():
diff --git a/accelerator/test_methods/a_test_dataset_unroundrobin.py b/accelerator/test_methods/a_test_dataset_unroundrobin.py
index 20d999a7..ed1c8e22 100644
--- a/accelerator/test_methods/a_test_dataset_unroundrobin.py
+++ b/accelerator/test_methods/a_test_dataset_unroundrobin.py
@@ -38,7 +38,7 @@ def synthesis(job, slices):
 	dw = job.datasetwriter(name='rr', columns=dict(a='int32', b='unicode'))
 	for sliceno in range(slices):
 		dw.set_slice(sliceno)
-		dw.write(sliceno, 'u %d' % (sliceno,))
+		dw.write(sliceno, f'u {sliceno}')
 		dw.write(sliceno, 'line 2')
 		dw.write(sliceno, 'line 3')
 		if sliceno == 0:
@@ -53,7 +53,7 @@ def want(a, b):
 			raise Exception(f'missing lines in {ds_unrr}')
 		assert got == (a, b), f"Wanted {(a, b)!r}, got {got!r} from {ds_unrr}"
 	for sliceno in range(slices):
-		want(sliceno, 'u %d' % (sliceno,))
+		want(sliceno, f'u {sliceno}')
 	for sliceno in range(slices):
 		want(sliceno, 'line 2')
 	for sliceno in range(slices):
@@ -70,7 +70,7 @@ def want(a, b):
 	imported = subjobs.build('csvimport', filename=exported.filename('unrr.csv'))
 	imported = subjobs.build('dataset_type', source=imported, column2type=dict(a='int32_10', b='ascii')).dataset()
 	for sliceno in range(slices):
-		assert list(imported.iterate(sliceno)) == list(ds_rr.iterate(sliceno)), "%s did not match %s in slice %d, export or import does not match roundrobin expectations" % (imported, ds_rr, sliceno)
+		assert list(imported.iterate(sliceno)) == list(ds_rr.iterate(sliceno)), f"{imported} did not match {ds_rr} in slice {sliceno}, export or import does not match roundrobin expectations"
 
 	# Check that empty slices in the middle are not a problem.
 	dw = job.datasetwriter(name='empty slices', columns=dict(a='number'))
diff --git a/accelerator/test_methods/a_test_hashlabel.py b/accelerator/test_methods/a_test_hashlabel.py
index 9458cff1..50045150 100644
--- a/accelerator/test_methods/a_test_hashlabel.py
+++ b/accelerator/test_methods/a_test_hashlabel.py
@@ -157,7 +157,7 @@ def synthesis(prepare_res, params, job, slices):
 			data = [(ds, list(ds.iterate(sliceno))) for ds in hl2ds[hashlabel]]
 			good = data[0][1]
 			for name, got in data:
-				assert got == good, "%s doesn't match %s in slice %d" % (data[0][0], name, sliceno,)
+				assert got == good, f"{data[0][0]} doesn't match {name} in slice {sliceno}"
 
 	# Verify that both up and down hashed on the expected column
 	hash = typed_writer("complex64").hash
@@ -165,7 +165,7 @@ def synthesis(prepare_res, params, job, slices):
 		ds = all_ds[colname + "_checked"]
 		for sliceno in range(slices):
 			for value in ds.iterate(sliceno, colname):
-				assert hash(value) % slices == sliceno, "Bad hashing on %s in slice %d" % (colname, sliceno,)
+				assert hash(value) % slices == sliceno, f"Bad hashing on {colname} in slice {sliceno}"
 
 	# Verify that up and down are not the same, to catch hashing
 	# not actually hashing.
@@ -193,7 +193,7 @@ def test_rehash(want_ds, chk_ds_lst):
 				assert chk_ds.hashlabel != want_ds.hashlabel
 				got = chk_ds.iterate(sliceno, hashlabel=want_ds.hashlabel, rehash=True)
 				got = sorted(cleanup(got))
-				assert want == got, "Rehashing is broken for %s (slice %d of %s)" % (chk_ds.columns[want_ds.hashlabel].type, sliceno, chk_ds,)
+				assert want == got, f"Rehashing is broken for {chk_ds.columns[want_ds.hashlabel].type} (slice {sliceno} of {chk_ds})"
 	test_rehash("up_checked", hl2ds[None] + hl2ds["down"])
 	test_rehash("down_checked", hl2ds[None] + hl2ds["up"])
 	test_rehash("up_datetime", [all_ds["down_time"]])
@@ -230,4 +230,4 @@ def test_rehash(want_ds, chk_ds_lst):
 		values = [(ds, list(ds.iterate(sliceno, "value"))) for ds in float_ds_lst]
 		want_ds, want = values.pop()
 		for ds, got in values:
-			assert got == want, "%s did not match %s in slice %d" % (ds, want_ds, sliceno,)
+			assert got == want, f"{ds} did not match {want_ds} in slice {sliceno}"
diff --git a/accelerator/test_methods/a_test_hashpart.py b/accelerator/test_methods/a_test_hashpart.py
index c496ae2f..94a0d473 100644
--- a/accelerator/test_methods/a_test_hashpart.py
+++ b/accelerator/test_methods/a_test_hashpart.py
@@ -83,12 +83,12 @@ def verify(slices, data, source, previous=None, **options):
 	for slice in range(slices):
 		for row in ds.iterate_chain(slice, names):
 			row = dict(zip(names, row))
-			assert h(row[hl]) % slices == slice, "row %r is incorrectly in slice %d in %s" % (row, slice, ds)
+			assert h(row[hl]) % slices == slice, f"row {row!r} is incorrectly in slice {slice} in {ds}"
 			want = good[row[hl]]
 			assert row == want, f'{ds} (rehashed from {source}) did not contain the right data for "{hl}".\nWanted\n{want!r}\ngot\n{row!r}'
 	want_lines = len(data)
 	got_lines = ds.chain().lines()
-	assert got_lines == want_lines, '%s (rehashed from %s) had %d lines, should have had %d' % (ds, source, got_lines, want_lines,)
+	assert got_lines == want_lines, f'{ds} (rehashed from {source}) had {got_lines} lines, should have had {want_lines}'
 	return ds
 
 def verify_empty(source, previous=None, **options):
@@ -131,7 +131,7 @@ def synthesis(params):
 	dw.write_dict(data[0])
 	ds = verify(params.slices, [data[0], data[0]], dw.finish(), hashlabel="date", chain_slices=True)
 	got_slices = len(ds.chain())
-	assert got_slices == params.slices, "%s (built with chain_slices=True) has %d datasets in chain, expected %d." % (ds, got_slices, params.slices)
+	assert got_slices == params.slices, f"{ds} (built with chain_slices=True) has {got_slices} datasets in chain, expected {params.slices}."
 
 	# test varying types and available columns over the chain (including the hashlabel type)
 	v1 = write([{'a': '101', 'b':  201 }], columns={'a': 'ascii',  'b': 'int32'}, name='varying1')
diff --git a/accelerator/test_methods/a_test_json.py b/accelerator/test_methods/a_test_json.py
index 93093b18..fdabf9fc 100644
--- a/accelerator/test_methods/a_test_json.py
+++ b/accelerator/test_methods/a_test_json.py
@@ -110,5 +110,5 @@ def synthesis():
 		if not sorted_s:
 			sorted_s = s
 			sorted_d = d
-		test("ordered%d.json" % (ix,), d, d, s, sort_keys=False)
-		test("sorted%d.json" % (ix,), d, sorted_d, sorted_s, sort_keys=True)
+		test(f"ordered{ix}.json", d, d, s, sort_keys=False)
+		test(f"sorted{ix}.json", d, sorted_d, sorted_s, sort_keys=True)
diff --git a/accelerator/test_methods/a_test_nan.py b/accelerator/test_methods/a_test_nan.py
index 110e6871..efb4f17c 100644
--- a/accelerator/test_methods/a_test_nan.py
+++ b/accelerator/test_methods/a_test_nan.py
@@ -104,7 +104,7 @@ def mk_dws(typ):
 		h = typed_writer(typ).hash
 		want_h = (want_hash_complex if typ.startswith('complex') else want_hash_float)
 		for ix, v in enumerate(values):
-			assert want_h == h(v), 'value index %d did not hash correctly for type %s' % (ix, typ,)
+			assert want_h == h(v), f'value index {ix} did not hash correctly for type {typ}'
 			w_u(str(ix), v)
 			w_h(str(ix), v)
 		ds_h = dw_h.finish()
diff --git a/accelerator/test_methods/a_test_number.py b/accelerator/test_methods/a_test_number.py
index 2daad305..482b8631 100644
--- a/accelerator/test_methods/a_test_number.py
+++ b/accelerator/test_methods/a_test_number.py
@@ -175,4 +175,4 @@ def endianfix(v):
 			('dataset_hashpart', ds_hashed),
 			('dataset_type', ds_typehashed),
 		]:
-			assert set(ds.iterate(sliceno, 'num')) == per_slice[sliceno], 'wrong in slice %d in %s (hashed by %s)' % (sliceno, ds, hashname)
+			assert set(ds.iterate(sliceno, 'num')) == per_slice[sliceno], f'wrong in slice {sliceno} in {ds} (hashed by {hashname})'
diff --git a/accelerator/test_methods/a_test_output.py b/accelerator/test_methods/a_test_output.py
index 06f21da6..afb992b5 100644
--- a/accelerator/test_methods/a_test_output.py
+++ b/accelerator/test_methods/a_test_output.py
@@ -39,13 +39,13 @@ def test(params, p=False, a=False, s=False):
 	cookie = randint(10000, 99999)
 	if p:
 		name += 'p'
-		opts['p'] = "Some words\nfrom prepare\nwith %d in them." % (cookie,)
+		opts['p'] = f"Some words\nfrom prepare\nwith {cookie} in them."
 	if a:
 		name += 'a'
 		opts['a'] = "A few words\nfrom analysis(%%d)\nwith the cookie %d in them." % (cookie,)
 	if s:
 		name += 's'
-		opts['s'] = "Words\nfrom synthesis\ncookie is %d." % (cookie,)
+		opts['s'] = f"Words\nfrom synthesis\ncookie is {cookie}."
 	jid = subjobs.build(name, options=opts)
 	d = jid.filename('OUTPUT/')
 	chked = set()
diff --git a/accelerator/test_methods/a_test_output_on_error.py b/accelerator/test_methods/a_test_output_on_error.py
index ba09438a..831560b4 100644
--- a/accelerator/test_methods/a_test_output_on_error.py
+++ b/accelerator/test_methods/a_test_output_on_error.py
@@ -30,7 +30,7 @@
 
 
 def synthesis():
-	lines = ['printing a bunch of lines, this is line %d.' % (n,) for n in range(150)]
+	lines = [f'printing a bunch of lines, this is line {n}.' for n in range(150)]
 	if options.inner:
 		for s in lines:
 			print(s)
@@ -51,6 +51,6 @@ def synthesis():
 						return
 			# not yet, wait a little (total of 30s)
 			if attempt > 1:
-				print('Output from %s has not appeared yet, waiting more (%d).' % (job, attempt,))
+				print(f'Output from {job} has not appeared yet, waiting more ({attempt}).')
 			sleep(attempt / 10.0)
 		raise Exception(f'Not all output from {job} was saved in OUTPUT')
diff --git a/accelerator/test_methods/a_test_rechain.py b/accelerator/test_methods/a_test_rechain.py
index 9816dd31..1f7429ee 100644
--- a/accelerator/test_methods/a_test_rechain.py
+++ b/accelerator/test_methods/a_test_rechain.py
@@ -34,7 +34,7 @@ def synthesis(job):
 	# build a local abf chain
 	prev = None
 	for ix, ds in enumerate(manual_abf):
-		name = "abf%d" % (ix,)
+		name = f"abf{ix}"
 		prev = ds.link_to_here(name, override_previous=prev)
 	manual_abf_data = list(Dataset.iterate_list(None, None, manual_abf))
 	local_abf_data = list(Dataset(job, "abf2").iterate_chain(None, None))
@@ -52,7 +52,7 @@ def synthesis(job):
 	while going:
 		if prev and "cache" in prev._data:
 			going = False
-		name = "longchain%d" % (ix,)
+		name = f"longchain{ix}"
 		dw = DatasetWriter(name=name, previous=prev)
 		dw.add("ix", "number")
 		dw.get_split_write()(ix)
diff --git a/accelerator/test_methods/a_test_shell_grep.py b/accelerator/test_methods/a_test_shell_grep.py
index ed615b54..963de00a 100644
--- a/accelerator/test_methods/a_test_shell_grep.py
+++ b/accelerator/test_methods/a_test_shell_grep.py
@@ -51,7 +51,7 @@ def grep_text(args, want, sep='\t', encoding='utf-8', unordered=False, check_out
 	want = [sep.join(typ(el) for el in l) for l in want]
 	for lineno, (want, got) in enumerate(zip(want, res), 1):
 		if want != got:
-			raise Exception('%r gave wrong result on line %d:\nWant: %r\nGot:  %r' % (cmd, lineno, want, got,))
+			raise Exception(f'{cmd!r} gave wrong result on line {lineno}:\nWant: {want!r}\nGot:  {got!r}')
 
 # like subprocess.check_output except stdout is a pty
 def check_output_pty(cmd):
@@ -86,9 +86,9 @@ def grep_json(args, want):
 		try:
 			got = json.loads(got)
 		except Exception as e:
-			raise Exception('%r made bad json %r on line %d: %s' % (cmd, got, lineno, e,))
+			raise Exception(f'{cmd!r} made bad json {got!r} on line {lineno}: {e}')
 		if want != got:
-			raise Exception('%r gave wrong result on line %d:\nWant: %r\nGot:  %r' % (cmd, lineno, want, got,))
+			raise Exception(f'{cmd!r} gave wrong result on line {lineno}:\nWant: {want!r}\nGot:  {got!r}')
 
 def mk_bytes(low, high):
 	return bytes(range(low, high))
@@ -320,7 +320,7 @@ def frame(framevalues, *a):
 	slice = 0
 	header_test = []
 	for ds_ix, cols in enumerate(columns):
-		dw = job.datasetwriter(name='header test %d' % (ds_ix,), previous=previous, allow_missing_slices=True)
+		dw = job.datasetwriter(name=f'header test {ds_ix}', previous=previous, allow_missing_slices=True)
 		for col in cols:
 			dw.add(col, col)
 		if sorted(cols) != previous_cols:
@@ -424,7 +424,7 @@ def frame(framevalues, *a):
 	# test escaping
 	unescaped, sliceno = header_test[-1]
 	escaped = unescaped.replace('\n', '\\n').replace('\r', '\\r').replace('"', '""')
-	grep_text(['-l', '-t', '/', '-S', '', previous], [['"%s"/%d' % (escaped, sliceno)]])
+	grep_text(['-l', '-t', '/', '-S', '', previous], [[f'"{escaped}"/{sliceno}']])
 
 	# more escaping
 	escapy = mk_ds('escapy',
diff --git a/accelerator/test_methods/a_test_sorting.py b/accelerator/test_methods/a_test_sorting.py
index 1d95ecaa..fceb7e24 100644
--- a/accelerator/test_methods/a_test_sorting.py
+++ b/accelerator/test_methods/a_test_sorting.py
@@ -83,7 +83,7 @@ def cmp(a, b):
 	for sliceno in range(slices):
 		good = sorted(test_data.sort_data_for_slice(sliceno), key=keycmp, reverse=reverse)
 		check = list(ds.iterate(sliceno))
-		assert unnan(check) == unnan(good), "Slice %d sorted on %s bad (%s)" % (sliceno, key, jid,)
+		assert unnan(check) == unnan(good), f"Slice {sliceno} sorted on {key} bad ({jid})"
 
 def synthesis(params):
 	source = Dataset(subjobs.build("test_sorting_gendata"))
diff --git a/accelerator/test_methods/a_test_status_in_exceptions.py b/accelerator/test_methods/a_test_status_in_exceptions.py
index 4cffe813..84a647b5 100644
--- a/accelerator/test_methods/a_test_status_in_exceptions.py
+++ b/accelerator/test_methods/a_test_status_in_exceptions.py
@@ -110,7 +110,7 @@ def synthesis(job):
 					want_re += '.*' + status1
 				for ix, want_line in enumerate(on_line, 1):
 					ds = job.dataset(str(len(on_line) - ix))
-					want_re += '.*Iterating %s:0 reached line %d\n' % (re.escape(ds.quoted), want_line,)
+					want_re += f'.*Iterating {re.escape(ds.quoted)}:0 reached line {want_line}\n'
 				if status2:
 					want_re += '.*' + status2
 				assert re.search(want_re, got, re.DOTALL), got
diff --git a/accelerator/test_methods/build_tests.py b/accelerator/test_methods/build_tests.py
index 67d945a2..27211aca 100644
--- a/accelerator/test_methods/build_tests.py
+++ b/accelerator/test_methods/build_tests.py
@@ -33,7 +33,7 @@
 '''
 
 def main(urd):
-	assert urd.info.slices >= 3, "The tests don't work with less than 3 slices (you have %d)." % (urd.info.slices,)
+	assert urd.info.slices >= 3, f"The tests don't work with less than 3 slices (you have {urd.info.slices})."
 
 	from accelerator.shell import cfg
 	# sys.argv[0] is absolute for unqualified commands ("ax"), but exactly what
@@ -135,10 +135,10 @@ def main(urd):
 			time_after = monotonic()
 		time_to_die = time_after - time_before
 		if time_to_die > 13:
-			print("test_analysis_died took %d seconds to die, it should be faster" % (time_to_die,))
+			print(f"test_analysis_died took {time_to_die} seconds to die, it should be faster")
 			exit(1)
 		elif time_to_die > 2:
-			print("test_analysis_died took %d seconds to die, so death detection is slow, but works" % (time_to_die,))
+			print(f"test_analysis_died took {time_to_die} seconds to die, so death detection is slow, but works")
 		else:
 			print(f"test_analysis_died took {time_to_die:.1f} seconds to die, so death detection works")
 
diff --git a/accelerator/unixhttp.py b/accelerator/unixhttp.py
index 72cdb0ef..672aa613 100644
--- a/accelerator/unixhttp.py
+++ b/accelerator/unixhttp.py
@@ -100,7 +100,7 @@ def call(url, data=None, fmt=json_decode, headers={}, server_name='server', retr
 		except HTTPError as e:
 			if resp is None and e.fp:
 				resp = e.fp.read().decode('utf-8')
-			msg = '%s says %d: %s' % (server_name, e.code, resp,)
+			msg = f'{server_name} says {e.code}: {resp}'
 			if server_name == 'urd' and 400 <= e.code < 500:
 				if e.code == 401:
 					err = UrdPermissionError()
@@ -123,7 +123,7 @@ def call(url, data=None, fmt=json_decode, headers={}, server_name='server', retr
 		if attempt < retries + 1:
 			time.sleep(attempt / 15)
 			if msg and not quiet:
-				print('Retrying (%d/%d).' % (attempt, retries,), file=sys.stderr)
+				print(f'Retrying ({attempt}/{retries}).', file=sys.stderr)
 	else:
 		if not quiet:
 			print('Giving up.', file=sys.stderr)
diff --git a/accelerator/urd.py b/accelerator/urd.py
index be38f85c..fa0ef03a 100644
--- a/accelerator/urd.py
+++ b/accelerator/urd.py
@@ -79,7 +79,7 @@ def __new__(cls, ts):
 		for part in ts.split('+'):
 			try:
 				integer = int(part, 10)
-				assert integer >= 0, 'Invalid timestamp %d' % (part,)
+				assert integer >= 0, f'Invalid timestamp {part}'
 				parts.append((0, integer,))
 				str_parts.append(str(integer))
 				continue
@@ -172,7 +172,7 @@ def __init__(self, path, verbose=True):
 			if verbose:
 				print("urd-list                          lines     ghosts     active")
 				for key, val in sorted(stat.items()):
-					print("%-30s  %7d    %7d    %7d" % (key, val, len(self.ghost_db[key]), len(self.db[key]),))
+					print(f"{key:30}  {val:7}    {len(self.ghost_db[key]):7}    {len(self.db[key]):7}")
 				print()
 		else:
 			print(f"Creating directory \"{path}\".")
diff --git a/dsutil/test.py b/dsutil/test.py
index f47031b7..0ef97063 100755
--- a/dsutil/test.py
+++ b/dsutil/test.py
@@ -114,7 +114,7 @@ def can_minmax(name):
 						raise Exception("Allowed None without none_support")
 				except (ValueError, TypeError, OverflowError):
 					assert ix < bad_cnt or (value is None and not test_none_support), repr(value)
-			assert fh.count == count, "%s: %d lines written, claims %d" % (name, count, fh.count,)
+			assert fh.count == count, f"{name}: {count} lines written, claims {fh.count}"
 			if can_minmax(name):
 				want_min = min(filter(lambda x: x is not None, res_data))
 				want_max = max(filter(lambda x: x is not None, res_data))
@@ -150,7 +150,7 @@ def can_minmax(name):
 						count += 1
 					except (ValueError, TypeError, OverflowError):
 						assert 0, f"No default: {value!r}"
-				assert fh.count == count, "%s: %d lines written, claims %d" % (name, count, fh.count,)
+				assert fh.count == count, f"{name}: {count} lines written, claims {fh.count}"
 			# No errors when there is a default
 			with r_mk(TMP_FN) as fh:
 				res = list(fh)
@@ -173,14 +173,14 @@ def slice_test(slices, spread_None):
 						assert hc == wrote, "Hashcheck disagrees with write"
 					except (ValueError, TypeError, OverflowError):
 						assert ix < bad_cnt, repr(value)
-				assert fh.count == count, "%s (%d, %d): %d lines written, claims %d" % (name, sliceno, slices, count, fh.count,)
+				assert fh.count == count, f"{name} ({sliceno}, {slices}): {count} lines written, claims {fh.count}"
 				if not forstrings(name):
 					got_min, got_max = fh.min, fh.max
 				fh.flush() # we overwrite the same file, so make sure we write.
 			total_count += count
 			with r_mk(TMP_FN) as fh:
 				tmp = list(fh)
-			assert len(tmp) == count, "%s (%d, %d): %d lines written, claims %d" % (name, sliceno, slices, len(tmp), count,)
+			assert len(tmp) == count, f"{name} ({sliceno}, {slices}): {len(tmp)} lines written, claims {count}"
 			for v in tmp:
 				assert (spread_None and v is None) or w_typ.hash(v) % slices == sliceno, f"Bad hash for {v!r}"
 				assert w_typ.hash(v) == _dsutil.hash(v), f"Inconsistent hash for {v!r}"
@@ -191,13 +191,13 @@ def slice_test(slices, spread_None):
 				if tmp:
 					want_min = min(tmp)
 					want_max = max(tmp)
-					assert got_min == want_min, "%s (%d, %d): claims min %r, not %r" % (name, sliceno, slices, got_min, want_min,)
-					assert got_max == want_max, "%s (%d, %d): claims max %r, not %r" % (name, sliceno, slices, got_max, want_max,)
+					assert got_min == want_min, f"{name} ({sliceno}, {slices}): claims min {got_min!r}, not {want_min!r}"
+					assert got_max == want_max, f"{name} ({sliceno}, {slices}): claims max {got_max!r}, not {want_max!r}"
 				else:
 					assert got_min is None and got_max is None
-		assert len(res) == total_count, "%s (%d): %d lines written, claims %d" % (name, slices, len(res), total_count,)
-		assert len(res) == len(res_data), "%s (%d): %d lines written, should be %d" % (name, slices, len(res), len(res_data),)
-		assert set(res) == set(res_data), "%s (%d): Wrong data: %r != %r" % (name, slices, res, res_data,)
+		assert len(res) == total_count, f"{name} ({slices}): {len(res)} lines written, claims {total_count}"
+		assert len(res) == len(res_data), f"{name} ({slices}): {len(res)} lines written, should be {len(res_data)}"
+		assert set(res) == set(res_data), f"{name} ({slices}): Wrong data: {res!r} != {res_data!r}"
 		# verify reading back with hashfilter gives the same as writing with it
 		with w_mk(TMP_FN, none_support=True) as fh:
 			for value in data[bad_cnt:]:
@@ -205,7 +205,7 @@ def slice_test(slices, spread_None):
 		for sliceno in range(slices):
 			with r_mk(TMP_FN, hashfilter=(sliceno, slices, spread_None)) as fh:
 				slice_values = list(compress(res_data, fh))
-			assert slice_values == sliced_res[sliceno], "Bad reader hashfilter: slice %d of %d gave %r instead of %r" % (sliceno, slices, slice_values, sliced_res[sliceno],)
+			assert slice_values == sliced_res[sliceno], f"Bad reader hashfilter: slice {sliceno} of {slices} gave {slice_values!r} instead of {sliced_res[sliceno]!r}"
 	for slices in range(1, 24):
 		slice_test(slices, False)
 		slice_test(slices, True)
@@ -220,7 +220,7 @@ def slice_test(slices, spread_None):
 					fh.write(value)
 			with r_mk(TMP_FN) as fh:
 				tmp = list(fh)
-				assert tmp == [None, None, None], "Bad spread_None %sfor %d slices" % ("from default " if "default" in kw else "", slices,)
+				assert tmp == [None, None, None], f"Bad spread_None {'from default ' if 'default' in kw else ''}for {slices} slices"
 			kw["default"] = None
 			value = object
 
@@ -260,8 +260,8 @@ def slice_test(slices, spread_None):
 	pass
 print("Hash testing, numbers")
 for v in (0, 1, 2, 9007199254740991, -42):
-	assert _dsutil.WriteInt64.hash(v) == _dsutil.WriteFloat64.hash(float(v)), "%d doesn't hash the same" % (v,)
-	assert _dsutil.WriteInt64.hash(v) == _dsutil.WriteNumber.hash(v), "%d doesn't hash the same" % (v,)
+	assert _dsutil.WriteInt64.hash(v) == _dsutil.WriteFloat64.hash(float(v)), f"{v} doesn't hash the same"
+	assert _dsutil.WriteInt64.hash(v) == _dsutil.WriteNumber.hash(v), f"{v} doesn't hash the same"
 
 print("Number boundary test")
 Z = 128 * 1024 # the internal buffer size in _dsutil
diff --git a/scripts/templates/a_check.py b/scripts/templates/a_check.py
index 15a26eda..5e23d346 100644
--- a/scripts/templates/a_check.py
+++ b/scripts/templates/a_check.py
@@ -4,7 +4,7 @@
 options = {'prefix': str, 'version': int}
 
 def check(num, *want):
-	job = Job('%s-%d' % (options.prefix, num))
+	job = Job(f'{options.prefix}-{num}')
 	assert job.params.version == options.version
 	assert job.params.versions.python_path
 	if job.params.version > 2:
@@ -14,7 +14,7 @@ def check(num, *want):
 	assert ds.lines == want_lines, f'{ds} should have had {want_lines!r} lines but has {ds.lines!r}'
 	for sliceno, want in enumerate(want):
 		got = list(ds.iterate(sliceno, ('a', 'b',)))
-		assert got == want, '%s slice %d should have had %r but had %r' % (ds, sliceno, want, got,)
+		assert got == want, f'{ds} slice {sliceno} should have had {want!r} but had {got!r}'
 
 def synthesis(job):
 	check(
@@ -37,9 +37,9 @@ def synthesis(job):
 	)
 	# Test for accidental recursion.
 	sys.setrecursionlimit(49)
-	ds51 = Job('%s-%d' % (options.prefix, 51)).dataset()
+	ds51 = Job(f'{options.prefix}-{51}').dataset()
 	assert len(ds51.chain()) == 50, f'{job} should have had a dataset chain of length 50'
 	# And check the chain actually contains the expected stuff (i.e. nothing past the first ds).
 	# (Also to check that iterating the chain doesn't recurse more.)
-	ds2 = Job('%s-%d' % (options.prefix, 2)).dataset()
+	ds2 = Job(f'{options.prefix}-{2}').dataset()
 	assert list(ds2.iterate(None)) == list(ds51.iterate_chain(None))
diff --git a/scripts/templates/a_verify.py b/scripts/templates/a_verify.py
index c4eb2bf7..c6c4a9d0 100644
--- a/scripts/templates/a_verify.py
+++ b/scripts/templates/a_verify.py
@@ -29,9 +29,9 @@ def analysis(sliceno):
 	good = test_data.sort_data_for_slice(sliceno)
 	for lineno, got in enumerate(jobs.source.dataset().iterate(sliceno)):
 		want = next(good)
-		assert nanfix(want) == nanfix(got), "Wanted:\n%r\nbut got:\n%r\non line %d in slice %d of %s" % (want, got, lineno, sliceno, jobs.source)
+		assert nanfix(want) == nanfix(got), f"Wanted:\n{want!r}\nbut got:\n{got!r}\non line {lineno} in slice {sliceno} of {jobs.source}"
 	left_over = len(list(good))
-	assert left_over == 0, "Slice %d of %s missing %d lines" % (sliceno, jobs.source, left_over,)
+	assert left_over == 0, f"Slice {sliceno} of {jobs.source} missing {left_over} lines"
 	if jobs.source.load()['py_version'] > 2 and sys.version_info[0] > 2:
 		assert list(jobs.source.dataset('pickle').iterate(sliceno, 'p')) == [{'sliceno': sliceno}]
 
@@ -40,9 +40,9 @@ def synthesis(job):
 	assert p.versions.accelerator == accelerator.__version__
 	with job.open_input('proj/accelerator.conf') as fh:
 		for line in fh:
-			if line.startswith('interpreters: p%d ' % (options.n,)):
+			if line.startswith(f'interpreters: p{options.n} '):
 				path = line.split(' ', 2)[2].strip()[1:-1]
 				break
 		else:
-			raise Exception('Failed to find interpreter #%d in accelerator.conf' % (options.n,))
+			raise Exception(f'Failed to find interpreter #{options.n} in accelerator.conf')
 	assert p.versions.python_path == path

From 3612e85d35ee0ef7091a234fa98e6c5757a99eea Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?=
 
Date: Thu, 28 Aug 2025 19:52:04 +0200
Subject: [PATCH 15/18] Use f-strings more aggressively instead of the "" + var
 pattern

It's shorter and more readable
---
 accelerator/board.py   | 18 +++++++++---------
 accelerator/build.py   | 24 ++++++++++++------------
 accelerator/dataset.py | 14 +++++++-------
 accelerator/extras.py  |  4 ++--
 4 files changed, 30 insertions(+), 30 deletions(-)

diff --git a/accelerator/board.py b/accelerator/board.py
index e6f34457..3aefc13f 100644
--- a/accelerator/board.py
+++ b/accelerator/board.py
@@ -77,7 +77,7 @@ def json_enc(value):
 def ax_repr(o):
 	res = []
 	if isinstance(o, JobWithFile):
-		link = '/job/' + bottle.html_escape(o.job)
+		link = f'/job/{bottle.html_escape(o.job)}'
 		res.append(f'JobWithFile(job=')
 		res.append(ax_repr(o.job))
 		name = bottle.html_escape(o.name)
@@ -147,8 +147,8 @@ def populate_hashed():
 			with open(os.path.join(dirname, filename), 'rb') as fh:
 				data = fh.read()
 			h = b64encode(sha1(data).digest(), b'_-').rstrip(b'=').decode('ascii')
-			h_name = h + '/' + filename
-			name2hashed[filename] = '/h/' + h_name
+			h_name = f'{h}/{filename}'
+			name2hashed[filename] = f'/h/{h_name}'
 			hashed[h_name] = (data, ctype,)
 		except OSError as e:
 			name2hashed[filename] = '/h/ERROR'
@@ -290,7 +290,7 @@ def call_s(*path, **kw):
 	def call_u(*path, **kw):
 		url = os.path.join(cfg.urd, *map(url_quote, path))
 		if kw:
-			url = url + '?' + urlencode(kw)
+			url = f'{url}?{urlencode(kw)}'
 		return call(url, server_name='urd')
 
 	# yield chunks of a file, optionally inserting some bonus content somewhere
@@ -626,7 +626,7 @@ def dataset_graph(dsid):
 	@bottle.get('/graph/urd///')
 	@view('rendergraph', prefer_ctype='image/svg+xml')
 	def urd_graph(user, build, ts):
-		key = user + '/' + build + '/' + ts
+		key = f'{user}/{build}/{ts}'
 		d = call_u(key)
 		ret = graph.graph(d, 'urd')
 		return ret
@@ -682,7 +682,7 @@ def urd():
 	@bottle.get('/urd///')
 	@view('urdlist', 'timestamps')
 	def urdlist(user, build):
-		key = user + '/' + build
+		key = f'{user}/{build}'
 		return dict(
 			key=key,
 			timestamps=call_u(key, 'since/0', captions=1),
@@ -691,9 +691,9 @@ def urdlist(user, build):
 	@bottle.get('/urd///')
 	@view('urditem', 'entry')
 	def urditem(user, build, ts):
-		key = user + '/' + build + '/' + ts
+		key = f'{user}/{build}/{ts}'
 		d = call_u(key)
-		key = user + '/' + build + '/' + d.timestamp
+		key = f'{user}/{build}/{d.timestamp}'
 		results = None
 		if d.get('build_job'):  # non-existing on older versions
 			try:
@@ -734,7 +734,7 @@ def error(e):
 		from pygments.formatters import HtmlFormatter
 	except Exception:
 		from accelerator.colour import bold, red, green
-		print(bold("\nINFO: Install \"pygments\" to have " + red("prett") + green("ified") + " source code in board.\n"))
+		print(bold(f"\nINFO: Install \"pygments\" to have {red('prett')}{green('ified')} source code in board.\n"))
 		highlight = None
 
 	bottle.TEMPLATE_PATH = [os.path.join(os.path.dirname(__file__), 'board')]
diff --git a/accelerator/build.py b/accelerator/build.py
index 5eec09f5..d3f1a35c 100644
--- a/accelerator/build.py
+++ b/accelerator/build.py
@@ -66,7 +66,7 @@ def __init__(self, server_url, verbose=False, flags=None, subjob_cookie=None, in
 		self.verbose = verbose
 		self.monitor = None
 		self.flags = flags or []
-		last_error = self._url_json('last_error?subjob_cookie=' + (subjob_cookie or ''))
+		last_error = self._url_json(f'last_error?subjob_cookie={subjob_cookie or ""}')
 		self.last_error_time = last_error.get('time')
 		# Workspaces should be per Automata
 		from accelerator.job import WORKDIRS
@@ -206,7 +206,7 @@ def _server_submit(self, json):
 		postdata = urlencode({'json': setupfile.encode_setup(json)}).encode('utf-8')
 		res = self._url_json('submit', data=postdata)
 		if 'error' in res:
-			raise ServerError('Submit failed: ' + res.error)
+			raise ServerError(f'Submit failed: {res.error}')
 		if 'why_build' not in res:
 			if not self.subjob_cookie:
 				self._printlist(res.jobs)
@@ -225,7 +225,7 @@ def _printlist(self, returndict):
 				link_msg = item.link
 			msg = f'   - {method:35} {make_msg:5} {link_msg}'
 			if item.make != True and 'total_time' in item:
-				msg = msg + ' ' + fmttime(item.total_time).rjust(78 - len(msg))
+				msg = f'{msg} {fmttime(item.total_time).rjust(78 - len(msg))}'
 			print(msg)
 
 	def method_info(self, method):
@@ -447,7 +447,7 @@ def _tsfix(ts):
 		assert isinstance(part, str_types), errmsg
 		parts.append(part)
 	parts = [TimeStamp(part) for part in parts]
-	return cmp + '+'.join(parts)
+	return f"{cmp}{'+'.join(parts)}"
 
 class Urd(object):
 	def __init__(self, a, info, user, password, horizon=None, default_workdir=None):
@@ -462,7 +462,7 @@ def __init__(self, a, info, user, password, horizon=None, default_workdir=None):
 		self.default_workdir = default_workdir
 		auth = f'{user}:{password}'
 		auth = b64encode(auth.encode('utf-8')).decode('ascii')
-		self._headers = {'Content-Type': 'application/json', 'Authorization': 'Basic ' + auth}
+		self._headers = {'Content-Type': 'application/json', 'Authorization': f'Basic {auth}'}
 		self._auth_tested = False
 		self._reset()
 
@@ -499,7 +499,7 @@ def _call(self, url, data=None, fmt=_urd_typeify):
 	def _get(self, path, *a):
 		assert self._current, "Can't record dependency with nothing running"
 		path = self._path(path)
-		assert path not in self._deps, 'Duplicate ' + path
+		assert path not in self._deps, f'Duplicate {path}'
 		url = '/'.join((self._url, path,) + a)
 		res = UrdResponse(self._call(url))
 		if res:
@@ -509,7 +509,7 @@ def _get(self, path, *a):
 
 	def _latest_str(self):
 		if self.horizon:
-			return '<=' + self.horizon
+			return f'<={self.horizon}'
 		else:
 			return 'latest'
 
@@ -589,7 +589,7 @@ def finish(self, path, timestamp=None, caption=None):
 		else:
 			timestamp = _tsfix(timestamp)
 		assert timestamp, f'No timestamp specified in begin or finish for {path}'
-		self._move_link_result(path + '/' + timestamp)
+		self._move_link_result(f'{path}/{timestamp}')
 		data = DotDict(
 			user=user,
 			build=build,
@@ -684,7 +684,7 @@ def find_automata(a, script):
 			package = [package]
 		else:
 			for cand in all_packages:
-				if cand.endswith('.' + package):
+				if cand.endswith(f'.{package}'):
 					package = [cand]
 					break
 			else:
@@ -692,9 +692,9 @@ def find_automata(a, script):
 	else:
 		package = all_packages
 	if not script.startswith('build'):
-		script = 'build_' + script
+		script = f'build_{script}'
 	for p in package:
-		module_name = p + '.' + script
+		module_name = f'{p}.{script}'
 		try:
 			module_ref = import_module(module_name)
 			return module_ref
@@ -743,7 +743,7 @@ def prepare_for_run(options, cfg):
 
 
 def run_automata(urd, options, cfg, module_ref, main_args):
-	url = 'allocate_job?' + urlencode({'workdir': options.workdir or '' })
+	url = f'allocate_job?{urlencode({"workdir": options.workdir or "" })}'
 	job = urd._a._url_json(url)
 	if 'error' in job:
 		print(job.error, file=sys.stderr)
diff --git a/accelerator/dataset.py b/accelerator/dataset.py
index df02c938..d9881315 100644
--- a/accelerator/dataset.py
+++ b/accelerator/dataset.py
@@ -87,7 +87,7 @@
 def _clean_name(n, seen_n):
 	n = ''.join(c if c.isalnum() else '_' for c in n)
 	if not n or n[0].isdigit():
-		n = '_' + n
+		n = f'_{n}'
 	while n in seen_n or iskeyword(n):
 		n += '_'
 	seen_n.add(n)
@@ -173,7 +173,7 @@ def _namechk(name):
 _dir_name_blacklist['\\'] = '\\\\' # make sure names can't collide
 
 def _fs_name(name):
-	return 'DS/' + ''.join(_dir_name_blacklist.get(c, c) for c in name)
+	return f'DS/{"".join(_dir_name_blacklist.get(c, c) for c in name)}'
 
 class Dataset(str):
 	"""
@@ -780,7 +780,7 @@ def _resolve_filters(columns, filters, want_tuple):
 					arg_n.append(n)
 					arg_v.append(f)
 					fs.append(f'{n}(t[{ix}])')
-			f = 'lambda t: ' + ' and '.join(fs)
+			f = f'lambda t: {" and ".join(fs)}'
 			# Add another lambda to put all fN into local variables.
 			# (This is faster than putting them in "locals", you get
 			# LOAD_DEREF instead of LOAD_GLOBAL.)
@@ -815,7 +815,7 @@ def fmt_dsname(d, sliceno, rehash):
 				sliceno = 'REHASH'
 			return f'{d.quoted}:{sliceno}'
 		if len(to_iter) == 1:
-			msg_head = 'Iterating ' + fmt_dsname(*to_iter[0])
+			msg_head = f'Iterating {fmt_dsname(*to_iter[0])}'
 			def update_status(ix, d, sliceno, rehash):
 				pass
 		else:
@@ -1431,7 +1431,7 @@ def write_dict(values):
 		w_d = dict(zip(w_names, w_l))
 		errcls = _clean_name('DatasetUsageError', used_names)
 		w_d[errcls] = DatasetUsageError
-		f = ['def write(' + ', '.join(names) + '):']
+		f = [f'def write({", ".join(names)}):']
 		f_list = ['def write_list(values):']
 		if len(names) == 1: # only the hashlabel, no check needed
 			f.append(f' {w_names[0]}({names[0]})')
@@ -1490,7 +1490,7 @@ def key(t):
 			return self._order.index(t[0])
 		def d2l(d):
 			return [w.write for _, w in sorted(d.items(), key=key)]
-		f_____ = ['def split(' + ', '.join(names) + '):']
+		f_____ = [f'def split({", ".join(names)}):']
 		f_list = ['def split_list(v):']
 		f_dict = ['def split_dict(d):']
 		from accelerator.g import slices
@@ -1572,7 +1572,7 @@ def discard(self):
 		if self._finished:
 			raise DatasetUsageError("Don't try to use writer after .finish()ing it")
 		del _datasetwriters[self.name]
-		self._finished = 'deleted dataset ' + self.name
+		self._finished = f'deleted dataset {self.name}'
 		from shutil import rmtree
 		rmtree(self.fs_name)
 
diff --git a/accelerator/extras.py b/accelerator/extras.py
index 382a9342..7cfcbf4a 100644
--- a/accelerator/extras.py
+++ b/accelerator/extras.py
@@ -207,7 +207,7 @@ def pickle_save(variable, filename='result.pickle', sliceno=None, temp=None, bac
 # default is 'ascii', which is pretty terrible too.)
 def pickle_load(filename='result.pickle', jobid=None, sliceno=None, encoding='bytes'):
 	filename = _fn(filename, jobid, sliceno)
-	with status('Loading ' + filename):
+	with status(f'Loading {filename}'):
 		with open(filename, 'rb') as fh:
 			return pickle.load(fh, encoding=encoding)
 
@@ -329,7 +329,7 @@ def __init__(self, filename, temp=None, _hidden=False):
 		self._hidden = _hidden
 
 	def __enter__(self):
-		self._status = status('Saving ' + self.filename)
+		self._status = status(f'Saving {self.filename}')
 		self._status.__enter__()
 		fh = getattr(self, '_open', open)(self.tmp_filename, 'xb')
 		self.close = fh.close

From c28f343cdf9f3effb8ca59d25e7be5a628c55c72 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?=
 
Date: Thu, 21 Aug 2025 14:38:14 +0200
Subject: [PATCH 16/18] [board] port some trivial functions to pathlib.Path

---
 accelerator/board.py | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/accelerator/board.py b/accelerator/board.py
index 3aefc13f..875b99a7 100644
--- a/accelerator/board.py
+++ b/accelerator/board.py
@@ -3,6 +3,7 @@
 #                                                                          #
 # Copyright (c) 2020-2024 Carl Drougge                                     #
 # Modifications copyright (c) 2024 Anders Berkeman                         #
+# Copyright (c) 2025 Pablo Correa Gomez                                    #
 #                                                                          #
 # Licensed under the Apache License, Version 2.0 (the "License");          #
 # you may not use this file except in compliance with the License.         #
@@ -29,6 +30,7 @@
 import mimetypes
 import time
 from stat import S_ISDIR, S_ISLNK
+from pathlib import Path
 
 from accelerator.job import Job, JobWithFile
 from accelerator.dataset import Dataset
@@ -137,15 +139,14 @@ def ax_link(v):
 def populate_hashed():
 	from hashlib import sha1
 	from base64 import b64encode
-	dirname = os.path.join(os.path.dirname(__file__), 'board')
+	dirname = Path(__file__).parent.joinpath('board')
 	for filename, ctype in [
 		('style.css', 'text/css; charset=UTF-8'),
 		('script.js', 'text/javascript; charset=UTF-8'),
 		('graph.js', 'text/javascript; charset=UTF-8'),
 	]:
 		try:
-			with open(os.path.join(dirname, filename), 'rb') as fh:
-				data = fh.read()
+			data = dirname.joinpath(filename).read_bytes()
 			h = b64encode(sha1(data).digest(), b'_-').rstrip(b'=').decode('ascii')
 			h_name = f'{h}/{filename}'
 			name2hashed[filename] = f'/h/{h_name}'
@@ -266,7 +267,7 @@ def run(cfg, from_shell=False, development=False):
 	global _development
 	_development = development
 
-	project = os.path.split(cfg.project_directory)[1]
+	project = Path(cfg.project_directory).name
 	setproctitle(f'ax board-server for {project} on {cfg.board_listen}')
 
 	# The default path filter (i.e. ) does not match newlines,
@@ -322,6 +323,7 @@ def file_parts_iter(parts, clen, fh, start=0, end=None, chunksize=128 * 1024):
 
 	# Based on the one in bottle but modified for our needs.
 	def static_file(filename, root, job=None):
+		# Should port to pathlib after https://github.com/bottlepy/bottle/issues/1311
 		root = os.path.abspath(root) + os.sep
 		filename = os.path.abspath(os.path.join(root, filename))
 		if not filename.startswith(root):
@@ -737,7 +739,7 @@ def error(e):
 		print(bold(f"\nINFO: Install \"pygments\" to have {red('prett')}{green('ified')} source code in board.\n"))
 		highlight = None
 
-	bottle.TEMPLATE_PATH = [os.path.join(os.path.dirname(__file__), 'board')]
+	bottle.TEMPLATE_PATH = [Path(__file__).parent.joinpath('board')]
 	kw = {}
 	if development:
 		kw['reloader'] = True

From 963a76afc04c17942d7ffbf5f757741dc5d03257 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?=
 
Date: Thu, 21 Aug 2025 15:20:15 +0200
Subject: [PATCH 17/18] [board] port results and job code-paths to use
 pathlib.Path

Uses across functions keep using strings, but at least simplifies
uses within functions
---
 accelerator/board.py | 45 ++++++++++++++++++++++----------------------
 1 file changed, 22 insertions(+), 23 deletions(-)

diff --git a/accelerator/board.py b/accelerator/board.py
index 875b99a7..d130988a 100644
--- a/accelerator/board.py
+++ b/accelerator/board.py
@@ -415,9 +415,9 @@ def results_contents(path):
 		res = {'files': files, 'dirs': dirs}
 		default_jobid = None
 		default_prefix = ''
-		prefix = cfg.result_directory
-		for part in path.strip('/').split('/'):
-			prefix = os.path.join(prefix, part)
+		prefix = Path(cfg.result_directory)
+		for part in Path(path).parts:
+			prefix = Path(prefix, part)
 			if not default_jobid:
 				try:
 					default_jobid, default_prefix = job_and_file(os.readlink(prefix), '')
@@ -427,35 +427,32 @@ def results_contents(path):
 					pass
 			elif default_prefix:
 				default_prefix += part + '/'
-		filenames = os.listdir(prefix)
-		for fn in filenames:
-			if fn.startswith('.') or fn.endswith('_'):
+		for fn in prefix.iterdir():
+			if fn.name.startswith('.') or fn.name.endswith('_'):
 				continue
-			ffn = os.path.join(prefix, fn)
 			try:
-				lstat = os.lstat(ffn)
+				lstat = fn.lstat()
 				if S_ISLNK(lstat.st_mode):
-					link_dest = os.readlink(ffn)
+					link_dest = os.readlink(fn)
 					stat = os.stat(link_dest)
-					jobid, name = job_and_file(link_dest, fn)
+					jobid, name = job_and_file(link_dest, fn.name)
 				else:
 					stat = lstat
 					jobid = default_jobid
-					name = default_prefix + fn
+					name = default_prefix + fn.name
 			except OSError:
 				continue
 			if S_ISDIR(stat.st_mode):
-				dirs[fn] = os.path.join('/results', path, fn, '')
+				dirs[fn.name] = Path('/results', path, fn.name).as_posix()
 			else:
-				files[fn] = dict(
+				files[fn.name] = dict(
 					jobid=jobid,
 					name=name,
 					ts=lstat.st_mtime,
 					size=stat.st_size,
 				)
 		if path:
-			a, b = os.path.split(path)
-			dirs['..'] = os.path.join('/results', a, '') if a else '/'
+			dirs['..'] = Path('/results', Path(path).parent).as_posix()
 		return res
 
 	@bottle.get('/results')
@@ -463,17 +460,18 @@ def results_contents(path):
 	@bottle.get('/results/')
 	def results(path=''):
 		path = path.strip('/')
-		if os.path.isdir(os.path.join(cfg.result_directory, path)):
+		abspath = Path(cfg.result_directory, path)
+		if abspath.is_dir():
 			accept = get_best_accept('text/html', 'application/json', 'text/json')
 			if accept == 'text/html':
-				return main_page(path=os.path.join('/results', path).rstrip('/'))
+				return main_page(path=Path('/results', path).as_posix())
 			else:
 				bottle.response.content_type = accept + '; charset=UTF-8'
 				bottle.response.set_header('Cache-Control', 'no-cache')
 				return json.dumps(results_contents(path))
 		elif path:
 			try:
-				link_dest = os.readlink(os.path.join(cfg.result_directory, path))
+				link_dest = os.readlink(abspath)
 				job, _ = job_and_file(link_dest, None)
 			except OSError:
 				job = None
@@ -529,9 +527,10 @@ def job_method(jobid, name=None):
 	@bottle.get('/job//')
 	def job_file(jobid, name):
 		job = name2job(cfg, jobid)
-		if os.path.isdir(job.filename(name)):
-			files = {fn for fn in os.listdir(job.filename(name))}
-			dirs = {dn for dn in files if os.path.isdir(job.filename(name + '/' + dn))}
+		fn = Path(job.filename(name))
+		if fn.is_dir():
+			files = {f.name for f in fn.iterdir()}
+			dirs = {dn for dn in files if fn.joinpath(dn).is_dir()}
 			files -= dirs
 			res = dict(dirs=sorted(dirs), files=sorted(files), dirname=name, job=job)
 			accept = get_best_accept('application/json', 'text/json', 'text/html')
@@ -559,7 +558,7 @@ def job(jobid):
 		if post:
 			aborted = False
 			files = {fn for fn in job.files() if fn[0] != '/'}
-			dirs = {dn for dn in files if os.path.isdir(job.filename(dn))}
+			dirs = {dn for dn in files if Path(job.filename(dn)).is_dir()}
 			files -= dirs
 			jobs = list(post.subjobs)
 			jobs.append(job)
@@ -582,7 +581,7 @@ def job(jobid):
 			job=job,
 			aborted=aborted,
 			current=current,
-			output=os.path.exists(job.filename('OUTPUT')),
+			output=Path(job.filename('OUTPUT')).exists(),
 			datasets=job.datasets,
 			params=job.params,
 			subjobs=subjobs,

From 93247f97eac7aac90868a9aafea2c7e5ef80c5a3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pablo=20Correa=20G=C3=B3mez?=
 
Date: Thu, 21 Aug 2025 15:43:01 +0200
Subject: [PATCH 18/18] [board] port job_and_file to use path and avoid more
 calls to os

---
 accelerator/board.py | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/accelerator/board.py b/accelerator/board.py
index d130988a..219b391a 100644
--- a/accelerator/board.py
+++ b/accelerator/board.py
@@ -391,14 +391,14 @@ def main_page(path='/results'):
 
 	# Look for actual workdirs, so things like /workdirs/foo/foo-37/foo-1/bar
 	# resolves to ('foo-37', 'foo-1/bar') and not ('foo-1', 'bar').
-	path2wd = {v: k for k, v in cfg.workdirs.items()}
+	path2wd = {Path(v): k for k, v in cfg.workdirs.items()}
 	def job_and_file(path, default_name):
-		wd = ''
-		path = iter(path.split('/'))
+		wd = Path('')
+		path = iter(path.parts)
 		for name in path:
 			if not name:
 				continue
-			wd = wd + '/' + name
+			wd.joinpath(name)
 			if wd in path2wd:
 				break
 		else:
@@ -420,7 +420,7 @@ def results_contents(path):
 			prefix = Path(prefix, part)
 			if not default_jobid:
 				try:
-					default_jobid, default_prefix = job_and_file(os.readlink(prefix), '')
+					default_jobid, default_prefix = job_and_file(prefix.readlink(), '')
 					if default_jobid and default_prefix:
 						default_prefix += '/'
 				except OSError:
@@ -433,8 +433,8 @@ def results_contents(path):
 			try:
 				lstat = fn.lstat()
 				if S_ISLNK(lstat.st_mode):
-					link_dest = os.readlink(fn)
-					stat = os.stat(link_dest)
+					link_dest = fn.readlink()
+					stat = link_dest.stat()
 					jobid, name = job_and_file(link_dest, fn.name)
 				else:
 					stat = lstat
@@ -471,8 +471,7 @@ def results(path=''):
 				return json.dumps(results_contents(path))
 		elif path:
 			try:
-				link_dest = os.readlink(abspath)
-				job, _ = job_and_file(link_dest, None)
+				job, _ = job_and_file(abspath.readlink(), None)
 			except OSError:
 				job = None
 			return static_file(path, root=cfg.result_directory, job=job)