大侠请留步！python 父过程怎样杀死子进程

大侠请留步！！！python 父进程怎样杀死子进程？
如题，希望在父进程退出时，杀掉所有子进程。

Python code

import multiprocessingfrom multiprocessing import Process, freeze_supportimport osimport sysimport timedef worker():        time.sleep(10)        print 'worker'def main():        processes = []                for i in range(2):                p = multiprocessing.Process(target=worker )                processes.append(p)        for i in range(2):                processes[i].start()        for i in range(2):                processes[i].join()if __name__ == '__main__':        freeze_support()        main()

Python code

>>> import multiprocessing, time, signal>>> p = multiprocessing.Process(target=time.sleep, args=(1000,))>>> print p, p.is_alive()<Process(Process-1, initial)> False>>> p.start()>>> print p, p.is_alive()<Process(Process-1, started)> True>>> p.terminate()>>> time.sleep(0.1)>>> print p, p.is_alive()<Process(Process-1, stopped[SIGTERM])> False>>> p.exitcode == -signal.SIGTERMTrue