# 2.装饰器运用的例题，模拟网上商城的验证功能。 user_list=[     {'name':'a','passwd':'123'},     {'name':'b','passwd':'123'},     {'name':'c','passwd':'123'},     {'name':'d','passwd':'123'}, ] user_static={'username':"",'login':False} def yanzheng(func):     def jiance(*args,**kwargs):         if user_static["username"] and user_static["login"]:             ret = func(*args, **kwargs)             return ret         username = input("请输入用户名：").strip()         userpasswd = input("请输入密码：").strip()         for user_dict in user_list:             if username==user_dict["name"] and userpasswd==user_dict["passwd"]:                 print("验证通过")                 user_static['username']=username                 user_static['login' ]=True                 ret=func(*args,**kwargs)                 return ret             else:                 print("输入用户名或密码有误，请重新输入")     return jiance @yanzheng def index(name):     print("欢迎【%s】来到XX购物网站" %(name)) @yanzheng def buycar(name):     print("欢迎【%s】购买的【%s】" % (name,["汽水，面包，白菜，鲜奶"])) def buy():     print("准备好结账吧") index("张三") buycar("张三")