如何利用python登录知乎页面？

import requests
from bs4 import BeautifulSoup

s = requests.Session()
r = s.post('http://www.zhihu.com/login',
           data={'_xsrf': BeautifulSoup(s.get('http://www.zhihu.com/').content).find(type='hidden')['value'],
                 'email': 'email', 'password': 'password', 'rememberme': 'y'})
print(r.text)