Python Context Managers code snippets

Python-Context-Managers/cm_demo.py

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+import os
+from contextlib import contextmanager
+
+
+@contextmanager
+def change_dir(destination):
+    try:
+        cwd = os.getcwd()
+        os.chdir(destination)
+        yield
+    finally:
+        os.chdir(cwd)
+
+
+with change_dir('Sample-Dir-One'):
+    print(os.listdir())
+
+with change_dir('Sample-Dir-Two'):
+    print(os.listdir())

Python-Context-Managers/sample.txt

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+Lorem ipsum dolor sit amet, consectetur adipiscing elit.

Python-Context-Managers/snippets.txt

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+
+class Open_File():
+
+    def __init__(self, destination):
+        pass
+
+    def __enter__(self):
+        pass
+
+    def __exit__(self, exc_type, exc_val, traceback):
+        pass
+
+
+#### Using contextlib ####
+
+@contextmanager
+def open_file(file, mode):
+    f = open(file, mode)
+    yield f
+    f.close()
+
+
+with open_file('sample.txt', 'w') as f:
+    f.write('Lorem ipsum dolor sit amet, consectetur adipiscing elit.')
+
+print(f.closed)
+
+
+#### CD Example ####
+
+cwd = os.getcwd()
+os.chdir('Sample-Dir-One')
+print(os.listdir())
+os.chdir(cwd)
+
+cwd = os.getcwd()
+os.chdir('Sample-Dir-Two')
+print(os.listdir())
+os.chdir(cwd)
+
+