python中关于装饰器的学习

import time
def timer(hello):
 def func(*args,**kwargs): #函数传参，不限个数。
 start = time.time()
 hello(*args,**kwargs) #函数传参，不限个数。
 end = time.time()
 print("运行时间：%s"%(end - start))
 return func
@timer
def hello():
 time.sleep(2)
 print("nihao")
hello()

import time
user = { #存储用户名和密码
 "luozeng":'123',
 "xuemanfei":'456',
 "xutian":'789'
}

def yanzheng(hello):
 def func(*args,**kwargs):
 start = time.time()
 username = input("请输入用户：").strip() #用户输入
 password = input("请输入密码：").strip()
 if username in user and password == user[username]: #用户名和密码验证
 print("登陆成功")
 hello(*args,**kwargs)
 else:
 exit("用户名或密码错误！")
 end = time.time()
 print("运行时间：%s"%(end - start))
 return func
@yanzheng
def hello():
 print("你好！")
hello()