python多线程交替打印abc以及线程池进程池的相关概念

import threading
import sys
import time
def showa():
    while True:
        lockc.acquire()   #获取对方的锁，释放自己的锁
        print('a',end='')
        sys.stdout.flush()   #释放缓冲区
        locka.release()
        time.sleep(0.2)
def showb():
    while True:
        locka.acquire()
        print('b',end='')
        sys.stdout.flush() 
        lockb.release()
        time.sleep(0.2)
def showc():
    while True:
        lockb.acquire()
        print('c',end='')
        sys.stdout.flush()
        lockc.release()
        time.sleep(0.2)
if __name__=='__main__':
    locka=threading.Lock()  #定义3个互斥锁
    lockb=threading.Lock()
    lockc=threading.Lock()
 
    t1=threading.Thread(target=showa)   #定义3个线程
    t2=threading.Thread(target=showb)
    t3=threading.Thread(target=showc)
 
    locka.acquire()   #先锁住a,b锁，保证先打印a
    lockb.acquire()
 
    t1.start()
    t2.start()
    t3.start()
 
执行结果：abcabcabcabcabcabcabcabcabcabcbabcabcabcabcabcabc.......