title: column selection and row filtering in one step
body: <p>How do you do</p>
  
  <p>column selection: </p>
  
  <pre><code>df[['A', 'C', 'D']]
  </code></pre>
  
  <p>and </p>
  
  <p>row filtering:</p>
  
  <pre><code>df[df['C'] &gt; 5]
  </code></pre>
  
  <p>in one step?</p>
  
  <p>I tried</p>
  
  <pre><code>df[df[['A', 'C', 'D']]['C'] &gt; 5]
  </code></pre>
  
  <p>but it did just the row filtering and brought back the columns I was trying to lose</p>