title: Python AES implementations difference
body: <p>I'm comparing AES implementations in Python from the <a href="http://pycrypto.org" rel="noreferrer">pycrypto</a> and the <a href="http://cryptography.io" rel="noreferrer">cryptography.io</a> library.</p>
  
  <pre><code>from cryptography.hazmat.primitives.ciphers import Cipher, modes, algorithms
  from cryptography.hazmat.backends import default_backend  # http://cryptography.io
  from Crypto.Cipher import AES  # http://pycrypto.org
  
  key = b'Sixteen byte key'
  iv = b'Sixteen byte ivv'
  cipher1 = AES.new(key, AES.MODE_CFB, iv)
  cipher2 = Cipher(algorithms.AES(key), modes.CFB(iv), default_backend())
  
  plaintext = b"Plaintext"
  
  print(cipher1.encrypt(plaintext))
  print(cipher1.decrypt(plaintext))
  print(cipher2.encryptor().update(plaintext))
  print(cipher2.decryptor().update(plaintext))
  </code></pre>
  
  <p>The MWE prints:</p>
  
  <pre><code>b'\xe4\xb4\xeb\xe3Si\x9ap\xee'
  b'7\xda\x98\xee\x05\xe4\xa0\xc7,'
  b'\xe4"\xd4mo\xa3;\xa9\xe0'
  b'\xe4"\xd4mo\xa3;\xa9\xe0'
  </code></pre>
  
  <p>Why are the outputs different?</p>