`requests`库提供了一个`session`类，来实现客户端与服务器的会话保持。 ```python # 实例化一个session对象 session = requests.session() # 让session发送get或post请求 response = session.get(url, headers) response = session.post(url, headers) ``` <br/> 案例：登录人人网 ```python import requests post_url = 'http://www.renren.com/PLogin.do' header = { 'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/77.0.3865.75 Safari/537.36' } # 1. 账号和密码 post_data = { 'email': '123456@qq.com', 'password': '123456' } # 2. 获取session对象 session = requests.session() # 3. 请求成功后，cookie会自动保存在session中 session.post(post_url, data=post_data, headers=header) # 4. 请求登陆之后的页面 response = session.get('http://www.renren.com/474133869/profile', headers=header) with open('renren.html', 'w', encoding='utf-8') as f: f.write(response.text) ```