curriculum/challenges/english/blocks/learn-string-manipulation-by-building-a-cipher/6555201d9b7fc917399f9f0b.md
The .isalpha() method returns True if all of the characters of the string on which it is called are letters. For example, the code below returns True:
'freeCodeCamp'.isalpha()
# True
Delete the condition char == ' ' and replace it by calling the .isalpha() method on char.
You should have if char.isalpha(): in your code.
({ test: () => assert.match(code, /if\s+char\.isalpha\s*\(\s*\)\s*:/) })
text = 'Hello Zaira!'
custom_key = 'python'
def vigenere(message, key, direction=1):
key_index = 0
alphabet = 'abcdefghijklmnopqrstuvwxyz'
final_message = ''
for char in message.lower():
--fcc-editable-region--
# Append space to the message
if char == ' ':
final_message += char
--fcc-editable-region--
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
encryption = vigenere(text, custom_key)
print(encryption)
decryption = vigenere(encryption, custom_key, -1)
print(decryption)