如何使用Python登录和抓取网站？

import requests
from bs4 import BeautifulSoup

login_url = 'https://example.com/login'
username = 'your_username'
password = 'your_password'

# 创建会话
session = requests.Session()

# 发送登录请求
login_data = {'username': username, 'password': password}
response = session.post(login_url, data=login_data)

# 检查登录是否成功
if response.status_code == 200:
    print('登录成功')
else:
    print('登录失败')

# 登录后的操作，例如抓取某个页面的数据
data_url = 'https://example.com/data'
response = session.get(data_url)

# 解析页面内容
soup = BeautifulSoup(response.content, 'html.parser')
# 进行数据提取或其他操作