title: beautifulsoup find_all() class shortcut doesn't work
body: <p>I am trying to find all <code>p</code> tags with the class <code>column</code>.</p>
  
  <pre><code>&lt;p class="column"&gt;This is a column&lt;/p&gt;
  &lt;p class="column"&gt;More columns heh&lt;/p&gt;
  </code></pre>
  
  <p>I tried doing:</p>
  
  <pre><code>soup.find_all(class_='column')
  </code></pre>
  
  <p>which returned <code>[]</code></p>
  
  <p>Then I tried:</p>
  
  <pre><code>soup.find_all(attrs={'class': 'column'})
  </code></pre>
  
  <p>and got the right results.</p>
  
  <p>Shouldn't these two statements be identical? What's the difference?</p>