Pip installation is too slow, resulting in non-stop retry, you can use the following command to install
pip install pymysql -i http://pypi.douban.com/simple --trusted-host pypi.douban.com
Other mirrors: Alibaba
Cloud http://mirrors.aliyun.com/pypi/simple/University of
Science and Technology of China https://pypi.mirrors.ustc.edu.cn/simple/douban
(douban) http://pypi.douban. com/simple/
Tsinghua University https://pypi.tuna.tsinghua.edu.cn/simple/University of
Science and Technology of China http://pypi.mirrors.ustc.edu.cn/simple/