#!usr/bin/env python
# -*- coding:utf-8 -*-
import time
def print_num(arg):
    time.sleep(1)
    print(arg)
#每秒打印一个数字，速度非常慢
for i in range(10):
    print_num(i)

#!usr/bin/env python
# -*- coding:utf-8 -*-
import time
import threading
def print_num(arg):
    time.sleep(1)
    print(arg)
#多线程打印速度很快
for i in range(10):
    t = threading.Thread(target=print_num, args=(i,))
    t.start()