Commonly used domestic sources are as follows:
Tsinghua University https://pypi.tuna.tsinghua.edu.cn/simple/
Alibaba Cloud http://mirrors.aliyun.com/pypi/simple/
University of Science and Technology of China https://pypi.mirrors.ustc.edu.cn/simple/
Douban http://pypi.douban.com/simple/
University of Science and Technology of China http://pypi.mirrors.ustc.edu.cn/simple/
Modify library download source in Pycharm
Just replace the domestic sources mentioned above.