def testa():
    sleep(1)
    print "a"

def testb():
    sleep(1)
    print "b"

testa()
testb()
#先隔出一秒打印出a，再过一秒打出b

ta = threading.Thread(target=testa)
tb = threading.Thread(target=testb)
for t in [ta,tb]:
    t.start()
for t in [ta,tb]:
    t.join()
print "DONE"

#输出是ab或者ba（紧贴着的）然后空一行再来DONE的结果。

#方法二：从Thread继承，并重写run()
class MyThread(threading.Thread):
    def __init__(self,arg):
        super(MyThread, self).__init__()#注意：一定要显式的调用父类的初始化函数。
        self.arg=arg
    def run(self):#定义每个线程要运行的函数
        time.sleep(1)
        print ‘the arg is:%s\r‘ % self.arg

for i in xrange(4):
    t =MyThread(i)
    t.start()

print ‘main thread end!‘

import threading  
    import Queue  
    import time  
    class worker(threading.Thread):  
     def __init__(self,queue):  
      threading.Thread.__init__(self)  
      self.queue=queue  
      self.thread_stop=False  
       
     def run(self):  
      while not self.thread_stop:  
       print("thread%d %s: waiting for tast" %(self.ident,self.name))  
       try:  
        task=q.get(block=True, timeout=20)#接收消息  
       except Queue.Empty:  
        print("Nothing to do!i will go home!")  
        self.thread_stop=True  
        break  
       print("task recv:%s ,task No:%d" % (task[0],task[1]))  
       print("i am working")  
       time.sleep(3)  
       print("work finished!")  
       q.task_done()#完成一个任务  
       res=q.qsize()#判断消息队列大小  
       if res>0:  
        print("fuck!There are still %d tasks to do" % (res))  
       
     def stop(self):  
      self.thread_stop = True  
       
    if __name__ == "__main__":  
     q=Queue.Queue(3)  
     worker=worker(q)  
     worker.start()  
     q.put(["produce one cup!",1], block=True, timeout=None)#产生任务消息  
     q.put(["produce one desk!",2], block=True, timeout=None)  
     q.put(["produce one apple!",3], block=True, timeout=None)  
     q.put(["produce one banana!",4], block=True, timeout=None)  
     q.put(["produce one bag!",5], block=True, timeout=None)  
     print("***************leader:wait for finish!")  
     q.join()#等待所有任务完成  
     print("***************leader:all task finished!")  

thread139958685849344 Thread-1: waiting for tast 1
    task recv:produce one cup! ,task No:1
    i am working
    work finished!
    fuck!There are still 3 tasks to do
    thread139958685849344 Thread-1: waiting for tast 1
    task recv:produce one desk! ,task No:2
    i am workingleader:wait for finish!
    work finished!
    fuck!There are still 3 tasks to do
    thread139958685849344 Thread-1: waiting for tast 1
    task recv:produce one apple! ,task No:3
    i am working
    work finished!
    fuck!There are still 2 tasks to do
    thread139958685849344 Thread-1: waiting for tast 1
    task recv:produce one banana! ,task No:4
    i am working
    work finished!
    fuck!There are still 1 tasks to do
    thread139958685849344 Thread-1: waiting for tast 1
    task recv:produce one bag! ,task No:5
    i am working
    work finished!
    thread139958685849344 Thread-1: waiting for tast 1
     ***************leader:all task finished!
    Nothing to do!i will go home!

for i in range(x):
  t = MyThread(queue)
  t.start()