httplib2 cookie 问题

Question

http = httplib2.Http()

try:
    login_url = 'http://www.zimuzu.tv/User/Login/ajaxLogin'
    login_params = {'account': '[e-mail]', 'password': '123456',
                    'remember': 1, 'url_back': 'http://www.zimuzu.tv/user/sign'}

    response, contents = http.request(login_url, method='POST', body=urlencode(login_params), headers=headers)
    headers['Cookie'] = response['set-cookie']  #保存cookie
    print('登陆返回状态', response['status'])
    contents_dict = eval(bytes.decode(contents))
    print(contents_dict)

    #签到页面
    response, contents = http.request(sign_url, headers=headers)
    #print('签到页面', response['status'])
    print(bytes.decode(contents))

为什么我这么写拿到的cookie不能访问下个页面,一直说我没登陆,是不是漏了什么东西啊?