from time import sleep
import multiprocessing

# a function that blocks for a moment
def task():
    print("first")
    q.put(1)
    q.get()
    print("third")

q = multiprocessing.Queue()

# create a process
p = multiprocessing.Process(target=task)
# run the process
p.start()
sleep(1)
aa = q.get()
print(f"Second, get {aa} from sub process")
q.put(2)
p.join()