python安装包国内镜像源

pip install -i https://pypi.doubanio.com/simple/ flask

pip install -i https://pypi.doubanio.com/simple/ -r requirements.txt

豆瓣 https://pypi.doubanio.com/simple/
网易 https://mirrors.163.com/pypi/simple/
阿里云 https://mirrors.aliyun.com/pypi/simple/
腾讯云 https://mirrors.cloud.tencent.com/pypi/simple
清华大学 https://pypi.tuna.tsinghua.edu.cn/simple/