function plus simple username password authentication

def renzheng(func): # Higher-order functions pass the function name func as a parameter 
    def wrapper(*args,** kwargs):
        username =input( ' Username: ' ).strip()
        passwd=input('密码：').strip()
        if username=='qwe' and passwd=='123':
           res = func(*args,** kwargs)
            return res
         else :
             print ( ' error ' )
     return wrapper 

@renzheng #Decorator def index ():
     print 
( ' Welcome to the homepage ' )
    home( " Little Li " )#Execute the home function after executing the authentication function once

@renzheng
def home(name):
     print ( ' Welcome home %s ' % name)
    shop( " Xiao Wang " ) #Execute the shop function after executing the authentication function once

@renzheng 
def shop(name): print ( ' %s has %s in the shopping cart, %s ' %(name, ' milk tea ' , ' sister ' )) 
　　index() #Execute the index function after executing the authentication function once

index() 
home() 
shop()