functionB的多线程直到函数A的线程完成才开始，但functionA的线程不等待functionB

import threading

def functionA():
    # 执行functionA的操作
    pass

def functionB():
    # 执行functionB的操作
    pass

def main():
    # 创建一个条件变量
    condition = threading.Condition()

    # 创建一个标志位，用于判断functionA是否完成
    is_A_finished = False

    def thread_A():
        nonlocal is_A_finished
        # 执行functionA的操作
        functionA()
        # 设置标志位为True
        is_A_finished = True
        # 通知等待的线程
        with condition:
            condition.notify()

    def thread_B():
        nonlocal is_A_finished
        # 等待functionA完成
        with condition:
            while not is_A_finished:
                condition.wait()
        # 执行functionB的操作
        functionB()

    # 创建线程A和线程B
    threadA = threading.Thread(target=thread_A)
    threadB = threading.Thread(target=thread_B)

    # 启动线程A和线程B
    threadA.start()
    threadB.start()

    # 等待线程A和线程B完成
    threadA.join()
    threadB.join()

# 调用主函数
main()