#!/usr/bin/env python# -*- coding: utf-8 -*-import threadfrom time import sleep, ctimeloops = [4,2]def loop(nloop, nsec, lock):    print ‘start loop ‘, nloop, ‘ at:‘, ctime()    sleep(nsec)    print ‘loop ‘, nloop, ‘ done at:‘,ctime()    lock.release()def main():    print ‘starting at:‘,ctime()    locks = []    nloops = range(len(loops))    for i in nloops:        lock = thread.allocate_lock()        lock.acquire()        locks.append(lock)    for i in nloops:        thread.start_new_thread(loop,(i,loops[i],locks[i]))    for i in nloops:        while locks[i].locked():            pass    print ‘all DONE at:‘, ctime()if __name__ == ‘__main__‘:    main()