编写装饰器, 为多个函数加上认证功能(用户的账户密码来源于文件, 用户有三次登录的机会), # 要求, 如果用户登录成功了, 后续就不需要再次登录了.

# flag = False # 一开始没有登录
#
# def login(): # 函数:对功能或者动作的封装
#     global flag
#     username = input("请输入你的用户名:")
#     password = input("请输入你的密码:")
#
#     with open("userinfo",mode="r", encoding="utf-8") as f:
#         for line in f:
#             dic = eval(line.strip())  # {"username":"wusir1", "password":"sb"}
#             if username == dic['username'] and password == dic['password']:
#                 print("登录成功")
#                 flag = True
#                 break
#         else:
#             print('登录失败')
#             flag = False
#
#
# def wrapper(fn):
#     def inner(*args, **kwargs):
#         count = 0
#         while count < 3:
#             if flag == True:
#                 ret = fn(*args, **kwargs)
#                 return ret
#             else: # 没登录
#                 login()
#                 count += 1
#     return inner
#
# @wrapper
# def func():
#     print("今天星期一. 你们啥时候睡觉啊")
#
#
# func()
# func()