title: What is inside SO file of Python library distribution?
body: <p>I <a href="http://usa.autodesk.com/adsk/servlet/pc/item?siteID=123112&amp;id=10775847" rel="nofollow noreferrer">have a library</a>, which consists of 3 files which are intended to be put in site python directory.</p>
  <pre><code>FbxCommon.py
  fbxsip.so
  fbx.so
  </code></pre>
  <p>Once these files are in place, Python can see <code>fbx</code> package. How does this system work? What is inside <code>SO</code> file?</p>
  <p>If it is a DLL how can it be python version-dependent (it works with python 3.3 but doesn't work with python 3.5)</p>
  <p><strong>UPDATE</strong></p>
  <p>Distinguishing code is following</p>
  <pre><code>from fbx import *
  lSdkManager = FbxManager.Create()
  </code></pre>
  <p>on Python 3.3 it just does nothing, while on Python 3.5 it throws this error:</p>
  <pre><code>Traceback (most recent call last):
    File &quot;/opt/pycharm-2017.2.2/helpers/pydev/pydevd.py&quot;, line 1599, in &lt;module&gt;
      globals = debugger.run(setup['file'], None, None, is_module)
    File &quot;/opt/pycharm-2017.2.2/helpers/pydev/pydevd.py&quot;, line 1026, in run
      pydev_imports.execfile(file, globals, locals)  # execute the script
    File &quot;/opt/pycharm-2017.2.2/helpers/pydev/_pydev_imps/_pydev_execfile.py&quot;, line 18, in execfile
      exec(compile(contents+&quot;\n&quot;, file, 'exec'), glob, loc)
    File &quot;/home/dims/PycharmProjects/FBXCheck/fbxcheck.py&quot;, line 2, in &lt;module&gt;
      lSdkManager = FbxManager.Create()
  AttributeError: type object 'FbxManager' has no attribute 'Create'
  </code></pre>