code: def aes_encrypt(value, secret, block_size=AES.block_size):
      
      iv = os.urandom(block_size * 2)
      cipher = AES.new(secret[:32], AES.MODE_CFB, iv[:block_size])
      return b'%s%s' % (iv, cipher.encrypt(value))
docs: AES encrypt @value with @secret using the |CFB| mode of AES
          with a cryptographically secure initialization vector.
  
          -> (#bytes) AES encrypted @value
  
          ..
              from vital.security import aes_encrypt, aes_decrypt
              aes_encrypt("Hello, world",
                          "aLWEFlwgwlreWELFNWEFWLEgwklgbweLKWEBGW")
              # -> 'zYgVYMbeOuiHR50aMFinY9JsfyMQCvpzI+LNqNcmZhw='
              aes_decrypt(
                  "zYgVYMbeOuiHR50aMFinY9JsfyMQCvpzI+LNqNcmZhw=",
                  "aLWEFlwgwlreWELFNWEFWLEgwklgbweLKWEBGW")
              # -> 'Hello, world'
          ..f