title: How to get first element in a list of tuples?
body: <p>I have a list like below where the first element is the id and the other is a string:</p>
  
  <pre><code>[(1, u'abc'), (2, u'def')]
  </code></pre>
  
  <p>I want to create a list of ids only from this list of tuples as below:</p>
  
  <pre><code>[1,2]
  </code></pre>
  
  <p>I'll use this list in <code>__in</code> so it needs to be a list of integer values.</p>