Problem 4 for pset 5 added

week_5/pset_5/problem_4.py

@@ -0,0 +1,11 @@
+# Problem 4 - Decrypt a Story
+
+# Now that you have all the pieces to the puzzle, please use them to decode the file story.txt.
+# The file ps6.py contains a helper function get_story_string() that returns the encrypted version of the story as a string.
+# Create a CiphertextMessage object using the story string and use decrypt_message to return the appropriate shift value and unencrypted story string.
+
+
+def decrypt_story():
+    encryptedStory = CiphertextMessage(get_story_string())
+    return encryptedStory.decrypt_message()
+