title: Joining pairs of elements of a list
body: <p>I know that a list can be joined to make one long string as in:</p>
  
  <pre><code>x = ['a', 'b', 'c', 'd']
  print ''.join(x)
  </code></pre>
  
  <p>Obviously this would output:</p>
  
  <pre><code>'abcd'
  </code></pre>
  
  <p>However, what I am trying to do is simply join the first and second strings in the list, then join the third and fourth and so on. In short, from the above example instead achieve an output of:</p>
  
  <pre><code>['ab', 'cd']
  </code></pre>
  
  <p>Is there any simple way to do this? I should probably also mention that the lengths of the strings in the list will be unpredictable, as will the number of strings within the list, though the number of strings will always be even. So the original list could just as well be: </p>
  
  <pre><code>['abcd', 'e', 'fg', 'hijklmn', 'opq', 'r'] 
  </code></pre>