Example code may be missing `if __name__ == '__main__'`

I stumbled upon a multiprocessing error when trying to run the example code and one of the warnings mentioned that could be because there was no if preventing the entry point code to run again and again after a fork.

Wrapping the example code around an `if __name__ == '__main__'` did the trick.


By the way, this is a very nice project. Thanks for sharing