python开启多个子进程并行运行的方法

from multiprocessing import Process
import sys, os
import time
def timetask(times):
  time.sleep(times)
  print time.localtime()
def works(func, arg, worknum):
  proc_record = []
  for i in range(worknum):
    p = Process(target = func, args = (arg,))
    p.start()
    proc_record.append(p)
  for p in proc_record:
    p.join()
if __name__ == '__main__':
  arg = 5
  procs = 4
  works(timetask, arg, procs)