一：编写函数，（函数执行的时间是随机的） 二：编写装饰器，为函数加上统计时间的功能

import timedef timmer(func):    def wrapper(*args,**kwargs):        start = time.time()        res = func(*args,**kwargs)        stop = time.time()        print('run time is %s' %(stop - start))        return res    return wrapper@timmerdef index():    print('welcome to index')    time.sleep(3)    return 123@timmerdef home(name):    print('welcome %s to home page' %name)    time.sleep(2)res = index()home('egon')

三：编写装饰器，为函数加上认证的功能

import timedef auth(func):    def wrapper(*args,**kwargs):        tag = True        while tag:            name_inp = input('username>>: ').strip()            pwd_inp = input('password>>: ')            with open('db','rt',encoding='utf-8') as f:                for line in f:                    line = line.strip('\n').split(':')                    if name_inp == line[0] and pwd_inp == line[1]:                        print('认证成功')                        tag = False                        break                else:                    print('认证失败')        res=func(*args,**kwargs)        return res    return wrapper@auth # index=auth(index)def index():    print('welcome to index')    time.sleep(3)    return 123@auth # home=auth(home)def home(name):    print('welcome %s to home page' %name)    time.sleep(2)res=index()home('egon')

四：编写装饰器，为多个函数加上认证的功能（用户的账号密码来源于文件），要求登录成功一次，后续的函数都无需再输入用户名和密码 注意：从文件中读出字符串形式的字典，可以用eval('{"name":"egon","password":"123"}')转成字典格式

db='db'login_status={
    'user':None,'status':False}def auth(auth_type='file'):    def auth2(func):        def wrapper(*args,**kwargs):            if login_status['user'] and login_status['status']:                return func(*args,**kwargs)            if auth_type == 'file':                with open(db,encoding='utf-8') as f:                    dic=eval(f.read())                name=input('username: ').strip()                password=input('password: ').strip()                if name in dic and password == dic[name]:                    login_status['user']=name                    login_status['status']=True                    res=func(*args,**kwargs)                    return res                else:                    print('username or password error')            elif auth_type == 'sql':                pass            else:                pass        return wrapper    return auth2@auth()def index():    print('index')@auth(auth_type='file')def home(name):    print('welcome %s to home' %name)index()home('egon')

五：编写装饰器，为多个函数加上认证功能，要求登录成功一次，在超时时间内无需重复登录，超过了超时时间，则必须重新登录

import time,randomuser={
    'user':None,'login_time':None,'timeout':0.000003,}def timmer(func):    def wrapper(*args,**kwargs):        s1=time.time()        res=func(*args,**kwargs)        s2=time.time()        print('%s' %(s2-s1))        return res    return wrapperdef auth(func):    def wrapper(*args,**kwargs):        if user['user']:            timeout=time.time()-user['login_time']            if timeout < user['timeout']:                return func(*args,**kwargs)        name=input('name>>: ').strip()        password=input('password>>: ').strip()        if name == 'egon' and password == '123':            user['user']=name            user['login_time']=time.time()            res=func(*args,**kwargs)            return res    return wrapper@authdef index():    time.sleep(random.randrange(3))    print('welcome to index')@authdef home(name):    time.sleep(random.randrange(3))    print('welcome %s to home ' %name)index()home('egon')