from multiprocessing import Process, Queue, Lock
import time

lock = Lock()


def f(q, a):
    lock.acquire()
    if a == 3:
        time.sleep(2)

        q.put(666)
        print('input')
    if a == 4:
        data = q.get()
        print(data)
    print(a)

    lock.release()


if __name__ == '__main__':
    q = Queue()
    p_list = []
    for i in range(8):
        p = Process(target=f, args=(q, i,))
        p_list.append(p)

    for p in p_list:
        p.start()

    print('-=------')

    for p in p_list:
        p.join()