python多线程处理大量文件数据

#! /usr/bin/env python
#encoding=utf-8
 
import threading
import time
from Queue import Queue
 
def readFile():
    file_object = open('/opt/dev/python/list.dat')
    global queue
    for line in file_object:                    
        queue.put(line)
 
class Consumer(threading.Thread):
    def run(self):
        global queue
        while queue.qsize() > 0:
            msg = self.name + '消费了 '+queue.get()
            print msg
            time.sleep(0.01)
 
queue = Queue()
def main():
    readFile()
    for i in range(5):
        c = Consumer()
        c.start()
 
if __name__ == '__main__':
    main()