title: Using pandas Data Frames, how to find repeated values in particular column?
body: <p>I have a Data Frame with multiple columns. I did dataFrame.groupby:</p>
  
  <pre><code>data_count = data.groupby('member_id')
  </code></pre>
  
  <p>I am unable to figure out next step to find rows with same member_id.</p>
  
  <p>I want to find count of repeated rows per category in 'member_id'.
  e.g.
  memer_id
  1
  1
  1
  2
  2
  The output should be 
  member_id         Count
  1                         3
  2                         2 </p>
  
  <p>P.S: I can think of thousands of workarounds like writing  loops and all. But what is the shortest way of doing this?</p>
  
  <p>This very basic Question . I referred to stackoverflow and the pandas documentation but it seems when it comes to python, Google search and documentation don't help much even to find basic functionality.</p>