title: Extracting value and creating new column out of it
body: <p>I would like to extract certain section of a URL, residing in a column of a Pandas Dataframe and make that a new column. This</p>
  
  <pre><code>ref = df['REFERRERURL']
  ref.str.findall("\\d\\d\\/(.*?)(;|\\?)",flags=re.IGNORECASE)
  </code></pre>
  
  <p>returns me a Series with tuples in it. How can I take out only one part of that tuple <em>before</em> the Series is created, so I can simply turn that into a column? Sample data for referrerurl is</p>
  
  <pre><code>http://wap.blah.com/xxx/id/11/someproduct_step2;jsessionid=....
  </code></pre>
  
  <p>In this example I am interested in creating a column that only has 'someproduct_step2' in it.</p>
  
  <p>Thanks, </p>