title: Filtering a Dictionary with mutiple keys and multiple values per key
body: <p>I have a question regarding how to filter a dictionary using a loop.</p>
  
  <p>Here is an example of the dictionary:</p>
  
  <pre><code>d = {'beta': ['ABC', '1', '5', '10', '15'],
       'lambda': ['DEF', '3', '30', '22.2', '150'],
       'omega': ['RST','15', '54.4', '150', '75']
  }
  </code></pre>
  
  <p>How do I filter the dictionary to remove keys if the 3rd value in each key is &lt; 100?  In other words, after the if function, only omega should be left in the dictionary.<br>
  I tried:</p>
  
  <pre><code>for k, v in d.iteritems(): 
      r = float((d[key][2]))
      if r &lt; float(100):
          del d[k]
  </code></pre>
  
  <p>But it did not work. Any thoughts? New to python programming here.</p>
  
  <p>The new dictionary should just leave the omega key since 150 is greater than 100.</p>