title: Python 2 and 3 compatible way of iterating through dict with key and value
body: <p>I have the following list comprehension that only works in Python 2 due to use of <code>iteritems()</code>:</p>
  
  <pre><code>foo = [key for key, value in some_dict.iteritems() if value['marked']]
  </code></pre>
  
  <p>I can't import any libraries. Is there a clean way of making this compatible on both Python 2 and 3?</p>