title: What does "setup.py clean" exactly do?
body: <p>Invoking a call to <code>setup</code> from <code>setuptools</code> with version 0.9.6 I can run the following command: </p>
  
  <pre><code>python setup.py clean
  </code></pre>
  
  <p>But what does this exactly do? The help on this command is a bit sparse, and running</p>
  
  <pre><code>python setup.py clean --all
  </code></pre>
  
  <p>gives useless statements like  </p>
  
  <pre><code>'build/lib.linux-i686-2.7' does not exist -- can't clean it
  </code></pre>
  
  <p>Is there a possibility to use this <code>clean</code> command to e.g. cleanup automatically temporary python files ending in <code>.pyc</code> and <code>.~</code>? Can this be done with this command, does it need to be configured, ...?</p>