title: Generate UUID for Cassandra in Python
body: <p>Heh,
  I'm using     </p>
  
  <p><code>cf.insert(uuid.uuid1().bytes_le, {'column1': 'val1'})</code>  (pycassa)</p>
  
  <p>to create a TimeUUID for Cassandra, but getting the error </p>
  
  <pre><code>InvalidRequestException: 
  InvalidRequestException(why='UUIDs must be exactly 16 bytes')
  </code></pre>
  
  <p>It doesn't work with</p>
  
  <pre><code>uuid.uuid1()
  uuid.uuid1().bytes
  str(uuid.uuid1())
  </code></pre>
  
  <p>either.</p>
  
  <p>What's the best way to create a valid TimeUUID to use with the CompareWith="TimeUUIDType" flag?</p>
  
  <p>Thanks,<br>
  Henrik</p>