title: ImportError: 'psMat' is not a built-in module
body: <p>I'm trying to build <a href="https://github.com/gregorio-project/gregorio/tree/release-3.0" rel="nofollow">gregorio</a>'s fonts, which involves running a Python script using fontforge bindings. The script is written for python2, but I've been unable to find python2 fontforge bindings (I'm running Arch Linux). When I run it with python3, it gives</p>
  
  <pre><code>ImportError: 'psMat' is not a built-in module
  </code></pre>
  
  <p>which I've never seen before, and I can't figure out what it means. (This is as opposed to</p>
  
  <pre><code>ImportError: No module named fontforge
  </code></pre>
  
  <p>when running under python2, which I know means that it can't find the module (as expected: the fontforge package only installs in <code>/usr/lib/python3.4/site-packages/</code>.)</p>
  
  <p>Specifically, the script tries to</p>
  
  <pre><code>import fontforge, psMat
  </code></pre>
  
  <p>but is only able to load the first one, regardless of which one is listed first.</p>
  
  <p>The only thing I've found that seems remotely related is <a href="https://stackoverflow.com/questions/26787674/c-class-not-recognized-by-python-3-as-a-module-via-boost-python-embedding">this stackoverflow question</a>, but as far as I can tell, fontforge.so and psMat.so are properly built for python3, as is also suggested by being able to load at least one of them.</p>