title: Pandas delete a row in a dataframe based on a value
body: <p>I want do delete rows in a pandas dataframe where a the second column = 0</p>
  <p>So this ...</p>
  <pre><code>  Code  Int
  0    A    0
  1    A    1
  2    B    1
  </code></pre>
  <p>Would turn into this ...</p>
  <pre><code>  Code  Int
  0    A    1
  1    B    1
  </code></pre>
  <p>Any help greatly appreciated!</p>