def decode_caesar_cipher(code, key):
    res = ''
    for ch in code:
        if 'a' <= ch <= 'z':
            res += chr((ord(ch) - ord('a') - key) % 26 + ord('a'))
        elif 'A' <= ch <= 'Z':
            res += chr((ord(ch) - ord('A') - key) % 26 + ord('A'))
        else:
            res += ch
    return res

test = "Khoor, Zruog"
print(decode_caesar_cipher(test, 3))  # Hello, World

code = input("code: ")
print(decode_caesar_cipher(code, 3))