This example is why I opened the issue for vectors around CAST non-ECB. :)

On Fri, Jan 3, 2014 at 5:45 PM, Alex Gaynor <notifications@github.com>
wrote:

>> @@ -198,6 +178,22 @@ Algorithms
>>      :param bytes key: The secret key, 40-128 bits in length (in increments of
>>                        8).  This must be kept secret.
>>  
>> +    Example encryption and decryption using
>> +    :class:`~cryptography.hazmat.primitives.ciphers.modes.ECB` mode:
> Examples using ECB mode violate our recommendation that all examples should use strong algorithm choices. Dangers of using ECB mode at a minimum need to be caleld out.
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