title: Disable python warnings only for specific module via commandline
body: <p>When starting my Python script I'm getting this warning:</p>
  
  <pre><code>/usr/lib/python2.7/dist-packages/cffi/model.py:526: UserWarning: 'point_conversion_form_t' has no values explicitly defined; next version will refuse to guess which integer type it is meant to be (unsigned/signed, int/long)
    % self._get_c_name())
  </code></pre>
  
  <p>I know I can ignore this warning like this:</p>
  
  <pre><code>PYTHONWARNINGS="ignore::UserWarning" python $MYSCRIPT
  </code></pre>
  
  <p>But this will also ignore UserWarnings from all other modules that I would still like to see.
  Is it possible to specify the ignore in a more fine-grained way, like passing the module name for which warnings should be suppressed?</p>