PST Gåte

from base64 import b64encode, b64decode
from Cryptodome.Cipher import AES
from Cryptodome.Util.Padding import pad, unpad

def get_primes(count):
    primes = [
  2,
  3,
  5,
  7,
  11,
  13,
  17,
  19,
  23,
  29,
  31,
  37,
  41,
  43,
  47,
  53,
  59,
  61,
  67,
  71,
  73,
  79,
  83,
  89,
  97,
  101,

]
    return(primes[0:count])

with open("plain.txt",'rb') as f:
    plaintext = f.read()

iv = ""
for i in get_primes(16):
    iv+= chr(plaintext[i+16])

key = b'\xba\xda\x55 HackerMan \x13\x37'

cipher = AES.new(key, AES.MODE_CBC, iv.encode('utf-8'))
decipher = cipher.decrypt(b64decode("/lb0WZDpaIDJVJwy+Q04LCqERqVj7AUItWGREJuXJeWtZN77yP6grehn1gRif31hjTEjLNFyxESweea81/QluWUyhZV9vmabm8NYkkSc6JJWuylGJKQJzA/wC2cM2ScrQQ8gV7GcnVyBCh7eq/N0jUm/L4xrX6IUIDi5CAkVZ9xSS5Tb4o01onOTbGWLd1EZwzZOMlq88wsTPZ6zY7dqj+LKq3Pj6SKlZfaR9eo6PXrRUOARCe9sQVtWVKc5DJfI"))

print(decipher.decode('utf-8'))