python多线程low版本

#!/usr/bin/env python
# -*- coding: utf-8 -*-
import  queue
import threading

class threadpool():
    def __init__(self,max_num):
        self.q = queue.Queue(max_num)
        for i in range(max_num):
            self.q.put(threading.Thread)

    def get_thread(self):
        return self.q.get()
    def add_thread(self):
        return self.q.put(threading.Thread)

pool = threadpool(5)

def func(i,pool):
    import  time
    time.sleep(1)
    print(i)
    pool.add_thread()

for i in range(30):
    thread = pool.get_thread()
    t = thread(target=func,args=(i,pool))
    t.start()