模拟登陆知乎

import re
from urllib import parse, request
import http.cookiejar
from PIL import Image
import time
import json

import ssl
ssl._create_default_https_context = ssl._create_unverified_context

# 建立LWPCookieJar实例，可以存Set-Cookie3类型的文件。
# 而MozillaCookieJar类是存为'.txt'格式的文件
cookie = http.cookiejar.LWPCookieJar('cookie')
# 若本地有cookie则不用再post数据了
try:
    cookie.load(ignore_discard=True)
except IOError:
    print('Cookie未加载！')

headers = {'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 '
                         '(KHTML, like Gecko) Chrome/57.0.2987.98 Safari/537.36',
           "Host": "www.zhihu.com",
           "Referer": "https://www.zhihu.com/",
           }
opener = request.build_opener(request.HTTPCookieProcessor(cookie))
# 给openner添加headers, addheaders方法接受元组而非字典
opener.addheaders = [(key, value) for key, value in headers.items()]


def get_xsrf():
    """
    获取参数_xsrf
    注意: 这部分试了几个代码获取不到，最后尝试从网站粘贴_xsrf，成功
    """
    response = opener.open('https://www.zhihu.com')
    html = response.read().decode('utf-8')
    get_xsrf_pattern = re.compile(r'