References: https://kirito.me/
https://github.com/Vespa314/bilibili-api/tree/e01dc0107bbf86133710189ad4b4b44b49aa1343
https://github.com/muzuiget/niconvert
How to run:
python bilibili.py av3087062
python acfun.py ac964455
aid: av id
cid: comment(danmu) id
pid: page id