heykarimoff · November 17, 2018 09:58 · Nov 17, 2018
diff --git a/context_manager.py b/context_manager.py
@@ -0,0 +1,34 @@
+import json
+from contextlib import contextmanager
+
+data = {'key': 1234}
+
+with open('the_json_file.json', 'wt') as json_file:
+	json.dump(data, json_file)	
+
+with OpenFile('the_json_file.json', 'wt') as json_file:
+	json.dump(data, json_file)	
+
+with open_file('the_json_file.json', 'wt') as json_file:
+	json.dump(data, json_file)	
+
+
+# Version 1
+class OpenFile:
+    def __init__(self, filename, mode):
+        self.filename = filename
+        self.mode = mode
+
+    def __enter__(self):
+        self.file = open(self.filename, self.mode)
+        return self.file
+
+    def __exit__(self):
+        self.file.close()
+
+# Version 2
+@contextmanager
+def open_file(filename, mode):
+    file = open(filename, mode)
+    yield file
+    file.close()