title: Use list item index as index to another list in python
body: <p>I have two lists:</p>
  <pre><code>A = ['PA', 'AT', 'TR']
  removlistv = ['TR', 'AI', 'IO', 'SO', 'CR', 'PH', 'RT']
  </code></pre>
  <p>I find the intersection of the two lists:</p>
  <pre><code>rm_nodes = set(A) &amp; set(removelistv)
  </code></pre>
  <p>Which creates the set <code>{'TR'}</code>. I now want to find the index of that intersection (or intersections) in the list <code>removelistv</code>:</p>
  <pre><code>indices = [removelistv.index(x) for x in rm_nodes]
  </code></pre>
  <p>So far so good, <code>indices</code> contains the correct value.
  The problem starts when I want to use the index value (which in this case is <code>[0]</code> i.e. a list) to retrieve the matching item in a third list <code>removelistst = ['TR0', 'AI1', 'IO1', 'SO0', 'CR1', 'PH0', 'RT1']</code>. My goal is to remove the item <code>'TR0'</code> from <code>removelistst</code>. Basically, I want to remove items from this list based on the output of the intersection of the two lists in the beginning.</p>
  <p>I've tried the following:</p>
  <pre><code>numbers =[ int(x) for x in indices ]
  removelistst[numbers]
  </code></pre>
  <p>Which returns the error:</p>
  <pre><code>TypeError: list indices must be integers or slices, not list
  </code></pre>