1.__call__方法的有意思的运用

#!/usr/bin/env python

import threading
from time import sleep, ctime

loops = [4, 2]

class ThreadFunc(object):
    def __init__(self, func, args, name=''):
        self.name = name
        self.func = func
        self.args = args

    def __call__(self):
        self.func(*self.args)

def loop(nloop, nsec):
    print 'start loop', nloop, 'at:', ctime()
    sleep(nsec)
    print 'loop', nloop, 'done at:', ctime()

def main():
    print 'starting at:', ctime()
    threads = []
    nloops = range(len(loops))

    for i in nloops:        # create all threads
        t = threading.Thread(
            target=ThreadFunc(loop, (i, loops[i]),
            loop.__name__))
        threads.append(t)

    for i in nloops:        # start all threads
        threads[i].start()

    for i in nloops:        # wait for completion
        threads[i].join()

    print 'all DONE at:', ctime()

if __name__ == '__main__':
    main()