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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def kill_process_children(pid):
 """Find and kill child processes of a process. :param pid: PID of parent process (process ID) :return: Nothing """

    if sys.platform == "darwin":
        kill_process_children_osx(pid)
    elif sys.platform == "linux":
        kill_process_children_unix(pid)
    else:
        pass