Update README.md

Author: themusharraf

README.md

@@ -318,7 +318,76 @@ import time
 #
 # hello()
 ```
+# Context Mangers
+```python
+# Context Managers
+# with open('file.txt', 'w') as file:
+# file.write("Hello")
+#
+# file = open('file,txt', 'w')
+# file.write('All Nc')
+# file.close()
+
+# class FileOpener:
+# def __init__(self, filename, mode='r'):
+# self.filename = filename,
+# self.mode = mode
+# self.opened_file = None
+#
+# def __enter__(self):
+# print("Entered")
+# return 1
+#
+# def __exit__(self, exc_type, exc_val, exc_tb):
+# print('Exited')
+#
+#
+# with FileOpener('file,txt', 'w') as file:
+# print('file', file)
+# print('nima_dir boldi')
+
+# class FileOpener:
+# def __init__(self, filename, mode='r'):
+# self.filename = filename
+# self.mode = mode
+# self.opened_file = None
+#
+# def __enter__(self):
+# print("Entered")
+# self.opened_file = open(self.filename, self.mode)
+# return self.opened_file
+#
+# def __exit__(self, exc_type, exc_val, exc_tb):
+# print('Exited')
+# if self.opened_file:
+# self.opened_file.close()
+#
+#
+# with FileOpener('file.txt', 'w') as file:
+# print('file', file)
+# file.write('All Nc')
+# raise Exception
+# print('nima_dir boldi')
+
+
+from contextlib import contextmanager
+
 
+@contextmanager
+def file_opener(filename, mode):
+ file = open(filename, mode)
+ print('open file')
+ try:
+ yield file
+ finally:
+ file.close()
+ print('closed file')
+
+
+with file_opener('files.txt', 'w') as file:
+ print('file', file)
+ raise Exception
+```
 # Typing modul
 
 ## Asosiy turlar