Correct several class getitem docs

And expand the text for tuples.

Co-authored-by: Jelle Zijlstra <906600+JelleZijlstra@users.noreply.github.com>

Author: sirosen

Doc/library/string.templatelib.rst

@@ -78,9 +78,6 @@ Types
       template.strings:  ('Ah! We do have ',              '.')
       template.values:   (                   'Camembert',    )
 
-   Templates are :ref:`generic <generics>` over the type of the values which
-   are interpolated.
-
    .. rubric:: Attributes
 
    .. attribute:: strings

Objects/genobject.c

@@ -1024,7 +1024,7 @@ static PyMethodDef gen_methods[] = {
     {"close", gen_close, METH_NOARGS, close_doc},
     {"__sizeof__", gen_sizeof, METH_NOARGS, sizeof__doc__},
     {"__class_getitem__", Py_GenericAlias, METH_O|METH_CLASS,
-     PyDoc_STR("generators are generic over the type of their values")},
+     PyDoc_STR("generators are generic over the types of their yield, send, and return values")},
     {NULL, NULL}        /* Sentinel */
 };
 
@@ -1376,7 +1376,7 @@ static PyMethodDef coro_methods[] = {
     {"close", gen_close, METH_NOARGS, coro_close_doc},
     {"__sizeof__", gen_sizeof, METH_NOARGS, sizeof__doc__},
     {"__class_getitem__", Py_GenericAlias, METH_O|METH_CLASS,
-     PyDoc_STR("coroutines are generic over the type of their return value")},
+     PyDoc_STR("coroutines are generic over the types of their yield, send, and return values")},
     {NULL, NULL}        /* Sentinel */
 };
 
@@ -1822,7 +1822,7 @@ static PyMethodDef async_gen_methods[] = {
     {"aclose", async_gen_aclose, METH_NOARGS, async_aclose_doc},
     {"__sizeof__", gen_sizeof, METH_NOARGS, sizeof__doc__},
     {"__class_getitem__",    Py_GenericAlias,
-    METH_O|METH_CLASS,       PyDoc_STR("async generators are generic over the type of their values")},
+    METH_O|METH_CLASS,       PyDoc_STR("async generators are generic over the types of their yield and send values")},
     {NULL, NULL}        /* Sentinel */
 };
 

Objects/sliceobject.c

@@ -563,7 +563,7 @@ static PyMethodDef slice_methods[] = {
     {"indices", slice_indices, METH_O, slice_indices_doc},
     {"__reduce__", slice_reduce, METH_NOARGS, reduce_doc},
     {"__class_getitem__", Py_GenericAlias, METH_O|METH_CLASS,
-     "slices are generic over the type of their values"},
+     "slices are generic over the types of their start, end, and step values"},
     {NULL, NULL}
 };
 

Objects/templateobject.c

@@ -376,7 +376,7 @@ static PyMethodDef template_methods[] = {
      // note that this is not supported in typeshed, and it is not clear if the
      // type for this is a simple TypeVar or a TypeVarTuple
      // for details, see: https://github.com/python/typeshed/issues/14878
-     PyDoc_STR("Templates are generic over the type of the values which are interpolated")},
+     PyDoc_STR("Template supports [] for generic usage")},
     {NULL, NULL},
 };
 

Objects/tupleobject.c

@@ -954,12 +954,18 @@ tuple___getnewargs___impl(PyTupleObject *self)
     return Py_BuildValue("(N)", tuple_slice(self, 0, Py_SIZE(self)));
 }
 
+
+PyDoc_STRVAR(tuple_class_getitem_doc,
+"Tuples are generic over the types of their contents.\n\
+The type arguments to a tuple should match the types and arity of the contents.\n\n\
+For example, use ``tuple[int, str]`` for a pair whose first element is an int and second element is a string.\n\n\
+Tuples also the form ``tuple[T, ...]`` to indicate an arbitrary length tuple of elements of type T.");
+
 static PyMethodDef tuple_methods[] = {
     TUPLE___GETNEWARGS___METHODDEF
     TUPLE_INDEX_METHODDEF
     TUPLE_COUNT_METHODDEF
-    {"__class_getitem__", Py_GenericAlias, METH_O|METH_CLASS,
-     PyDoc_STR("tuples are generic over the types of their contents, with type arguments which match the types and arity of their contents")},
+    {"__class_getitem__", Py_GenericAlias, METH_O|METH_CLASS, tuple_class_getitem_doc},
     {NULL,              NULL}           /* sentinel */
 };