What if you need to actually have truly parallel code, that has the ability to run on multiple cores? Because Python has the GIL, you need to move away from using threads and go to using separate processes to handle the different tasks. Luckily, Python includes a multiprocessing module that provides the process equivalent to the threading module. As with the threading module, you create a new process object and hand in a target function to be run. You then need to call the start() method to get it running. With threads, sharing data is trivial because memory is global and everybody can see everything.
However, different processes are in different memory scopes. In order to share data, we need to explicitly set up some form of communications. You can…
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The Python Book (Digital) - 1 Issue, The Python Book 16th Edition