Python 进程池的同步方法

import time
from multiprocessing import Process,Pool

def f1(n):
    time.sleep(1)
    #print(n)
    return n*n

if __name__ == '__main__':
    pool = Pool(4)
    for i in range(10):
        print("xxxx")
        res = pool.apply(f1,args=(i,))
        print(res)