title: How to force pip uninstall in case of missing files
body: <p>I need to remove a corrupted old version of <code>setuptools</code> package from pip</p>
  
  <p>unfortunately <code>pip uninstall setuptools</code> </p>
  
  <p>doesn't work because cannot find some entries and returns me: </p>
  
  <pre><code>Cannot remove entries from nonexistent file ...
  </code></pre>
  
  <p>errors</p>
  
  <p>For the install procedure you can use <code>--ignore-installed</code> to continue the operation anyway for uninstalling procedure this flag seems not recognized. </p>
  
  <p>What command should use to achieve the package deletion?</p>