title: Combine two columns of text in pandas dataframe
body: <p>I have a 20 x 4000 dataframe in Python using pandas. Two of these columns are named <code>Year</code> and <code>quarter</code>. I'd like to create a variable called <code>period</code> that makes <code>Year = 2000</code> and <code>quarter= q2</code> into <code>2000q2</code>.</p>
  
  <p>Can anyone help with that?</p>