RuntimeError: Attempt to start a new process before the current process has finished its bootstrapping phase. This probably means that you are on Windows and you have forgotten to use the proper idiom in the main module: if name == ‘main’: freeze_support() … The “freeze_support()” line can be omitted if the program is not going to be frozen to produce a Windows executable.
Solution
As the note said, add __main__`` guard and add
freeze_support()` and the begining.
1if __name__ == "__main__":2 # multiprocessing.freeze_support() # may be not needed3 start = time.time()4 ...
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