豆瓣模拟登录

import requests
from lxml import etree
import re

url="https://www.douban.com/accounts/login"

headers={'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.100 Safari/537.36'}

s=requests.session()
r=s.get(url,headers=headers)
html=etree.HTML(r.text)

capurl=html.xpath('//*[@id="captcha_image"]/@src')[0]
print(capurl)
i=re.findall('\?id=(.*?)\&size',capurl)[0]
capid=i
cap=input("输入验证码：")

data={
    'source':'index_nav',
    'form_email':'srx963@163.com',
    'form_password':';,.sun1129',
    'captcha-solution':cap,
    'captcha-id':capid
}
r2=s.post(url,data=data,headers=headers,allow_redirects=True)
print(r2.text)