Upgrade:
Python install --upgrade PIP PIP -m -i https://pypi.tuna.tsinghua.edu.cn/simple/
PIP:
PIP install -i https://pypi.tuna.tsinghua.edu.cn/simple --trusted-host pypi.tuna.tsinghua.edu.cn xlwings
or
pip install xlwings-i https://pypi.tuna.tsinghua.edu.cn/simple
