1.安装python3
https://blog.csdn.net/elija940818/article/details/79238813?utm_medium=distribute.pc_relevant.none-task-blog-OPENSEARCH-1.control&depth_1-utm_source=distribute.pc_relevant.none-task-blog-OPENSEARCH-1.control
https://blog.csdn.net/longzhoufeng/article/details/109879818
2.链接pip3
python3自带pip3，软连接一下就能用
ln -s /usr/local/bin/python3/bin/pip3 /usr/bin/pip3
centos安装 requirements.txt 失败