Learn String Manipulation by Building a Cipher - Step 90

Hi Guys,

i cant figure out what the problem is ?
Can somebody help me because im stuck at this problem for 2 days.
I tried everything, pls help.

Your code so far

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

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)

# User Editable Region

print(f'Encrypted text: {text}')
print(f'Key: ' + custom_key)

# User Editable Region

#decryption = decrypt(encryption, custom_key)
#print(decryption)

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36 OPR/109.0.0.0

Challenge Information:

Learn String Manipulation by Building a Cipher - Step 90

as you are using an f-string, you should interpolate custom_key and not use the contatenation anymore

Thanks for the grate help