title: Add multiple columns with zero values from a list to a Pandas data frame
body: <p>Say I have a data frame </p>
  
  <pre><code>id col1 col2
  1  1    foo
  2  1    bar
  </code></pre>
  
  <p>And a list of column names</p>
  
  <pre><code>l = ['col3', 'col4', 'col5']
  </code></pre>
  
  <p>How do I add new columns to the data frame with zero as values?</p>
  
  <pre><code>id col1 col2 col3 col4 col5
  1  1    foo     0    0    0
  2  1    bar     0    0    0
  </code></pre>