清华源地址
https://mirror.baidu.com/pypi/simple
单个模块添加源地址
pip install '模块名' -i https://mirror.baidu.com/pypi/simple
requirements添加源地址
pip install -r requirements.txt -i https://mirror.baidu.com/pypi/simple
requirements安装并升级
pip install --upgrade -r requirements.txt -i https://mirror.baidu.com/pypi/simple
