# Learn String Manipulation by Building a Cipher - Step 95

### Tell us what’s happening:

I am not sure whether i’m supposed to change every custom_key to happycoding or only a few, but nothing seems to pass.

``````
# User Editable Region

text = 'mrttaqrhknsw ih puggrur'
custom_key = 'python'

print('\nEncrypted text:', text)
print(f'Key: {custom_key}')

def vigenere(message, key, direction=1):
key_index = 0
alphabet = 'abcdefghijklmnopqrstuvwxyz'
final_message = ''

for char in message.lower():

# Append any non-letter character to the message
if not char.isalpha():
final_message += char
else:
# Find the right key character to encode/decode
key_char = key[key_index % len(key)]
key_index += 1

# Define the offset and the encrypted/decrypted letter
offset = alphabet.index(key_char)
index = alphabet.find(char)
new_index = (index + offset*direction) % len(alphabet)
final_message += alphabet[new_index]

return final_message

def encrypt(message, key):
return vigenere(message, key)

def decrypt(message, key):
return vigenere(message, key, -1)

encryption = encrypt(text, custom_key)
print('Encrypted text:', encryption)

decryption = decrypt(encryption, 'happycoding')
print('Decrypted text:', decryption)

# User Editable Region

``````

User Agent is: `Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36`

### Challenge Information:

Learn String Manipulation by Building a Cipher - Step 95

`custom_key` is assigned on line two.

Happy coding

WOW! Can’t believe I tried everything, but this! Thanks a bunch!!! Haha

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