进程之间不共享资源的原因

import multiprocessing
import time
g_list = list()
def add_list():
    for i in range(1, 5):
        g_list.append(i)
        time.sleep(0.2)
        print(i)
        pass
    pass
def read_list():
    print(g_list)
if __name__ == '__main__':
    add_process = multiprocessing.Process(target=add_list)
    read_process = multiprocessing.Process(target=read_list)
    add_process.start()
    # join 是当前进程下（主进程），只有当子进程执行完成之后，才得以往下执行
    add_process.join()
    read_process.start()
    print(g_list)