title: How to iterate over Pandas Series generated from groupby().size()
body: <p>How do you iterate over a Pandas Series generated from a <code>.groupby('...').size()</code> command and get both the group name and count.</p>
  <p>As an example if I have:</p>
  <pre><code>foo
  -1     7
   0    85
   1    14
   2     5
  </code></pre>
  <p>how can I loop over them so that in each iteration I would have -1 &amp; 7, 0 &amp; 85, 1 &amp; 14 and 2 &amp; 5 in variables?</p>
  <p>I tried the enumerate option but it doesn't quite work.  Example:</p>
  <pre><code>for i, row in enumerate(df.groupby(['foo']).size()):
      print(i, row)
  </code></pre>
  <p>it doesn't return -1, 0, 1, and 2 for <code>i</code> but rather 0, 1, 2, 3.</p>