title: Pandas loc multiple conditions
body: <p>I have a dataframe and I want to delete all rows where column A is equal to blue and also col B is equal to green.</p>
  
  <p>I though the below should work, but its not the case.</p>
  
  <p>Can anyone see the problem</p>
  
  <pre><code>df=df.loc[~(df['A']=='blue' &amp; df['B']=='green')]
  </code></pre>