title: What is a SwigPyObject objects?
body: <p>I get an error when I try to save a custom object with </p>
  
  <p><code>with open(path + '/' + 'my_object.pickle', 'wb') as handle:
              pickle.dump(my_class_instance, handle, protocol=pickle.HIGHEST_PROTOCOL)</code></p>
  
  <p>The error message is:</p>
  
  <blockquote>
    <p>TypeError: can't pickle SwigPyObject objects</p>
  </blockquote>
  
  <p>My first question is: <strong>What is a SwigPyObject objects?</strong>, so I can try to figured out where the errors came from.</p>