How to implement Python to crawl website code examples that require login

import requests
from lxml import html
# 创建 session 对象。这个对象会保存所有的登录会话请求。
session_requests = requests.session()
# 提取在登录时所使用的 csrf 标记
login_url = "https://bitbucket.org/account/signin/?next=/"
result = session_requests.get(login_url)
tree = html.fromstring(result.text)
authenticity_token = list(set(tree.xpath("//input[@name='csrfmiddlewaretoken']/@value")))[0]
payload = {
  "username": "<你的用户名>",
  "password": "<你的密码>",
  "csrfmiddlewaretoken": authenticity_token # 在源代码中，有一个名为 “csrfmiddlewaretoken” 的隐藏输入标签。
}
# 执行登录
result = session_requests.post(
  login_url,
  data = payload,
  headers = dict(referer=login_url)
)
# 已经登录成功了，然后从 bitbucket dashboard 页面上爬取内容。
url = &#39;https://bitbucket.org/dashboard/overview&#39;
result = session_requests.get(
  url,
  headers = dict(referer = url)
)
# 测试爬取的内容
tree = html.fromstring(result.content)
bucket_elems = tree.findall(".//span[@class=&#39;repo-name&#39;]/")
bucket_names = [bucket.text_content.replace("n", "").strip() for bucket in bucket_elems]
print(bucket_names)