title: python: break list into pieces when an empty entry is found
body: <p>Lets say I have a list that looks like:</p>
  
  <pre><code>[
    [],
    ['blah','blah'],
    ['a','b'],
    [],
    ['abc','2'],
    ['ff','a'],
    ['test','a'],
    [],
    ['123','1'],
    []
  ]
  </code></pre>
  
  <p>How do I break this list into list of lists when it encounters an empty item</p>
  
  <p>so list[0] would have :</p>
  
  <pre><code>['blah','blah']
  ['a','b']
  </code></pre>
  
  <p>list[1] would have:</p>
  
  <pre><code>['abc','2']
  ['ff','a']
  ['test','a']
  </code></pre>