add decryption function

index.py

@@ -19,9 +19,11 @@ def encrypt(text, key):
     return cipher_text
 
 
-def decrypt():
-    greet = '\nhello decryption'
-    return greet
+def decrypt(text, key):
+    # make decrypter
+    decrypter = AES.new(key, AES.MODE_CFB)
+    plain_text = decrypter.decrypt(text)
+    return plain_text
 
 
 def main():
@@ -36,14 +38,20 @@ def main():
     # read the text file in and make it a string with no line breaks
     text = args.file.read().replace('\n', '')
 
+    # print encrypted text
+    print("Original file contents:")
+    print(text)
+
     # encrypt the file
     encrypted_text = encrypt(str.encode(text), key)
 
     # print encrypted text
-    print("Encrypted file created. Contents:")
+    print("\nEncrypted file created. Contents:")
     print(encrypted_text)
 
-    print(decrypt())
+    # decrypt and print decrypted text
+    print("\nDecrypted file. Contents:")
+    print(decrypt(encrypted_text, key))
 
 
 if __name__ == '__main__':