title: Extracting text from elements in Pandas column, writing to new column
body: <p>I've got some data in a column (COL_NAME) of a Pandas DataFrame.  I'd like to extract some text between '(' and ')' (this data either exists, or the parens don't exist at all, although there may be more than one set of parens in the data).  I'd then like to write the data in the paren to another column, and then remove the '(XXX)' from the original string.</p>
  
  <p>I.e.</p>
  
  <pre><code>COL_NAME
  ========
  (info) text (yay!)
  I love text
  Text is fun
  (more info) more text
  lotsa text (boo!)
  </code></pre>
  
  <p>turns in to:</p>
  
  <pre><code>COL_NAME          NEW_COL
  ========          =======
  text (yay!)       info
  i love text       None
  Text is fun       None
  more text         more info
  lots text (boo!)  None
  </code></pre>
  
  <p>I can do this by isolating the column, iterating through its elements, splitting on the (, creating two new lists and then adding them to the DataFrame, but there's assuredly a way more Pythonic/Pandic way of doing this, right?</p>
  
  <p>Thanks!  </p>