The “freeze_support()“ line can be omitted if the program

报错信息如下：
RuntimeError:
An attempt has been made to start a new process before the
current process has finished its bootstrapping phase.
This probably means that you are not using fork to start your
child processes 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最先出现在Python成神之路。