Problem4.py

#Problem 4 - Decrypt a Story

#For this problem, the graders will use our implementation of the Message, PlaintextMessage, and CiphertextMessage 
# classes, so don't worry if you did not get the previous parts correct.

# 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.

# Paste your function decrypt_story() in the box below.

def decrypt_story():
    str=get_story_string()
    decrypt=CiphertextMessage(str)
    k=decrypt.decrypt_message()
    return k