create pip mirror
python3 -m venv bandersnatch
bandersnatch/bin/pip install bandersnatch
bandersnatch/bin/bandersnatch --help

当时pip的完全mirror，需要7.9T左右，在执行前需要有相应的disk和网络带宽

https://pypi.org/stats/
https://github.com/pypa/bandersnatch/
https://packaging.python.org/guides/index-mirrors-and-caches/