You are using pip version 19.3.1; however, version 20.0.2 is available. You should con

You are using pip version 19.3.1; however, version 20.0.2 is available. You should con
使用管理员权限的命令行也不行，但是后来再来一次就可以了

python -m pip install -U --force-reinstall pip

但这个代码会更快

pip install -i http://e.pypi.python.org --trusted-host e.pypi.python.org --upgrade pip

You are using pip version 19.3.1; however, version 20.0.2 is available. You should con
但后来导入第三方库的时候又遇到了timed out

推荐：
pip install -i http://pypi.douban.com/simple --trusted-host pypi.douban.com packagename # packagename是要下载的包的名字
pip install -i http://e.pypi.python.org --trusted-host e.pypi.python.org --upgrade pip # 升级pip

You are using pip version 19.3.1; however, version 20.0.2 is available. You should con
速度很快。