title: Python AES key value greater than 128
body: <p>I used the following example to use AES with python: <a href="https://gist.github.com/gustavohenrique/79cc95cc351d975a075f18a5c9f49319" rel="nofollow noreferrer">AES criptography</a>. I modified the key to something like that:</p>
  
  <pre><code>key='\x61\x62\x53\x54\x55\x66\x67\x68\x69\x70\x71\x32\x33\x74\x75\x76'
  </code></pre>
  
  <p>This works fine. Note that all these hex-values are less than 128 and so they can represented within the ascii-table. When i change one value to <code>\x80</code> or higher i got this error message:</p>
  
  <pre><code>ValueError: AES key must be either 16, 24, or 32 bytes long
  </code></pre>
  
  <p>On my embedded device (in c) i can use a value greater than 128.</p>