#!/usr/bin/env python3
from Cryptodome.Cipher import AES
from base64 import b64decode

KEY = b'931069B52546C2DF278CD52EE695D4F2'


def decode(enc):
    enc = b64decode(enc)
    return enc[16:], enc[0:16]


def decipher(enc, iv):
    cipher = AES.new(KEY, AES.MODE_CBC, iv=iv)
    return cipher.decrypt(enc)


if __name__ == '__main__':
    from sys import argv
    enc, iv = decode(argv[1])
    print(decipher(enc, iv))