Session 5 - Natallia Paliashchuk

NatalliaPaliashchuk/hw5.py

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+# Homework-5_Working-with-data.md
+# Совместный доступ
+# P
+# Свойства системы
+# Тип
+# Текст
+# Размер
+# 3 КБ
+# Занимает
+# 3 КБ
+# Расположение
+# Session 5
+# Владелец
+# Python Training
+# Изменено
+# 29 мар. 2022 г. (Python Training)
+# Открыто
+# 21:52 (я)
+# Создано
+# 28 апр. 2022 г.
+# Описания нет
+# Читателям разрешено скачивать файл
+# # Python Practice - Session 4
+
+
+# ### Task 4.1
+# Open file `data/unsorted_names.txt` in data folder. Sort the names and write them to a new file called `sorted_names.txt`. Each name should start with a new line as in the following example:
+
+# ```
+# Adele
+# Adrienne
+# ...
+# Willodean
+# Xavier
+# ```
+with open('data/unsorted_names.txt', 'r') as file, open('sorted_names.txt', 'w') as file_2:
+    for name in sorted(file.readlines()):
+        if '\n' in name:
+            file_2.write(name)
+        else:
+            file_2.write(name + '\n')
+
+
+# ### Task 4.2
+# Implement a function which search for most common words in the file.
+# Use `data/lorem_ipsum.txt` file as a example.
+
+# ```python
+# def most_common_words(filepath, number_of_words=3):
+#     pass
+
+# print(most_common_words('lorem_ipsum.txt'))
+# >>> ['donec', 'etiam', 'aliquam']
+# ```
+
+# > NOTE: Remember about dots, commas, capital letters etc.
+def most_common_words(filepath, number_of_words=3):
+    table = {39: 32, 34: 32, 46: 32, 44: 32, 63: 32, 33: 32, 58: 32, 59: 32, 92: 32, 47: 32}
+    result = {}
+    with open(filepath, 'r') as file:
+        for line in file:
+            for word in line.lower().translate(table).split():
+                result[word] = result.get(word, 0) + 1
+    return [word for word in sorted(result, key=lambda x: result[x], reverse=True)][:number_of_words]
+
+
+# ### Task 4.3
+# File `data/students.csv` stores information about students in [CSV](https://en.wikipedia.org/wiki/Comma-separated_values) format.
+# This file contains the student’s names, age and average mark. 
+# 1) Implement a function which receives file path and returns names of top performer students
+# ```python
+# def get_top_performers(file_path, number_of_top_students=5):
+#     pass
+
+# print(get_top_performers("students.csv"))
+# >>> ['Teresa Jones', 'Richard Snider', 'Jessica Dubose', 'Heather Garcia', 'Joseph Head']
+def get_top_performers(file_path, number_of_top_students=5):
+    result = []
+    with open(file_path, 'r') as file:
+        for line in file:
+            name, _, mark = line.split(sep=',')
+            result.append((name, mark))
+    return [name[0] for name in sorted(result[1:], key=lambda x: float(x[1]), reverse=True)][:number_of_top_students]
+# ```
+
+# 2) Implement a function which receives the file path with srudents info and writes CSV student information to the new file in descending order of age. 
+# Result:
+# ``` 
+# student name,age,average mark
+# Verdell Crawford,30,8.86
+# Brenda Silva,30,7.53
+# ...
+# Lindsey Cummings,18,6.88
+# Raymond Soileau,18,7.27
+# ```
+def age_write_performers(file_path):
+    result = []
+    with open(file_path, 'r') as file:
+        for line in file:
+            name, age, mark = line.split(sep=',')
+            result.append((name, age, mark))
+    with open(file_path[:-4] + '_new.csv', 'w') as file:
+        file.write(','.join(result[0]))
+        for line in [name for name in sorted(result[1:], key=lambda x: x[1], reverse=True)]:
+            file.write(','.join(line))
+
+
+# ### Task 4.4
+# Look through file `modules/legb.py`.
+
+# 1) Find a way to call `inner_function` without moving it from inside of `enclosed_function`.
+a = "I am global variable!"
+
+
+def enclosing_funcion():
+    a = "I am variable from enclosed function!"
+
+    def inner_function():
+
+
+        a = "I am local variable!"
+        print(a)
+
+    return inner_function   
+
+# 2.1) Modify ONE LINE in `inner_function` to make it print variable 'a' from global scope.
+a = "I am global variable!"
+
+
+def enclosing_funcion():
+    a = "I am variable from enclosed function!"
+
+    def inner_function():
+
+        global a
+
+        print(a)
+
+    return inner_function   
+
+# 2.2) Modify ONE LINE in `inner_function` to make it print variable 'a' form enclosing function.
+a = "I am global variable!"
+
+
+def enclosing_funcion():
+    a = "I am variable from enclosed function!"
+
+    def inner_function():
+
+
+        nonlocal a
+        print(a)
+
+
+    return inner_function   
+
+
+# ### Task 4.5
+# Implement a decorator `remember_result` which remembers last result of function it decorates and prints it before next call.
+
+# ```python
+# @remember_result
+# def sum_list(*args):
+# 	result = ""
+# 	for item in args:
+# 		result += item
+# 	print(f"Current result = '{result}'")
+# 	return result
+
+# sum_list("a", "b")
+# >>> "Last result = 'None'"
+# >>> "Current result = 'ab'"
+# sum_list("abc", "cde")
+# >>> "Last result = 'ab'" 
+# >>> "Current result = 'abccde'"
+# sum_list(3, 4, 5)
+# >>> "Last result = 'abccde'" 
+# >>> "Current result = '12'"
+# ```
+def remember_result(func):
+    result = None
+    def wrapper(*args):
+        nonlocal result
+        print(f"Last result = '{result}'")
+        result = func(*args)
+
+    return wrapper
+
+# ### Task 4.6
+# Implement a decorator `call_once` which runs a function or method once and caches the result.
+# All consecutive calls to this function should return cached result no matter the arguments.
+
+# ```python
+# @call_once
+# def sum_of_numbers(a, b):
+#     return a + b
+
+# print(sum_of_numbers(13, 42))
+# >>> 55
+# print(sum_of_numbers(999, 100))
+# >>> 55
+# print(sum_of_numbers(134, 412))
+# >>> 55
+# print(sum_of_numbers(856, 232))
+# >>> 55
+# ```
+def call_once(func):
+    result = None
+    def wrapper(*args, **kwargs):
+        nonlocal result
+        if result == None:
+           result = func(*args, **kwargs)
+        return result
+    return wrapper
+
+
+
+# ### Task 4.7*
+# Run the module `modules/mod_a.py`. Check its result. Explain why does this happen.
+# Try to change x to a list `[1,2,3]`. Explain the result.
+# Try to change import to `from x import *` where x - module names. Explain the result. 
+
+
+# ### Materials
+# * [Decorators](https://realpython.com/primer-on-python-decorators/)
+# * [Decorators in python](https://www.geeksforgeeks.org/decorators-in-python/)
+# * [Python imports](https://pythonworld.ru/osnovy/rabota-s-modulyami-sozdanie-podklyuchenie-instrukciyami-import-i-from.html)
+# * [Files in python](https://realpython.com/read-write-files-python/)