pip default download third-party libraries from Python official website, of course not as good as from abroad comes from domestic download download
Watercress: https: //pypi.doubanio.com/simple
There are other sources, Ali cloud, etc., enough to use a
When installed with pip library, followed by the transducer -i represents a source, and then enter the address on
pip install *** -i https://pypi.doubanio.com/simple