Format Markdown to Html style by Python and GitHub API

markdown_to_html.py

import requests

contents = ''
with open("a.md") as f:
    contents = f.readlines()

sum = ''
for content in contents:
  sum += content

print(sum)
res = requests.post(headers={
      "Accept": "application/vnd.github+json",
      "Authorization": "token GITHUB_KEY"
    }, url="https://api.github.com/markdown",
    json={"text": sum})
print(res.status_code)
print(res.text)