title: Python UTC timestamp with ISO format
body: <p>I know this has been asked but there was no solution provided there.
  <a href="https://stackoverflow.com/questions/19654578/python-utc-datetime-objects-iso-format-dont-include-z-zulu-or-zero-offset">Python UTC datetime object&#39;s ISO format doesn&#39;t include Z (Zulu or Zero offset)</a></p>
  
  <p>I am looking for a <em>clean</em> way of generating UTC time stamp with this format in Python. The format I need is
  <code>2013-10-29T09:38:41.341Z</code>. </p>
  
  <p>Specifically, I need to include "Z" at the end. Python's <code>datetime.utcnow().isoformat()</code> does not append "Z" at the end.</p>
  
  <p>Note that manually appending "Z" is not a solution I can accept. I am looking for a clean way to do this.</p>
  
  <p>What is the clean way to generate UTC timestamp in ISO format with the suffix <code>Z</code>?</p>