多进程

import multiprocessing,time

def down_load():
   time.sleep(5)
   print("运行完了")


if __name__ == '__main__':

   for i in range(5):
      p = multiprocessing.Process(target=down_load)
      p.start()
   while len(multiprocessing.active_children())!=0:#等待子进程结束
      pass
   # print(multiprocessing.active_children())

   print(multiprocessing.current_process())
   print('end')