title: Turn flat list into two-tuples
body: <p>Is there a single line expression to accomplish the following:</p>
  
  <pre><code>input = ['this', 'is', 'a', 'list']
  output = [('this', 'is'), ('a', 'list')]
  </code></pre>
  
  <p>My initial idea was to create two lists and then zip them up. That would take three lines.</p>
  
  <p>The list will have an even number of elements.</p>