一，安装python3.9.1
参考文章
https://www.cnblogs.com/xiujin/p/11477419.html
在root用户下(不要用普通用户,麻烦)
yum -y groupinstall "Development tools"
yum -y install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel gdbm-devel db4-devel libpcap-devel xz-devel
yum install -y libffi-devel zlib1g-dev
yum install zlib* -y
直接使用wget下载安装包。（wget下载慢,尝试过使用mwget，但是不稳定。所以慢点就慢点）
wget wget https://www.python.org/ftp/python/3.9.1/Python-3.9.1.tar.xz
解压
tar -xvJf Python-3.9.1.tar.xz
创建编译安装目录
mkdir /usr/local/python3
安装
cd Python-3.9.1
./configure --prefix=/usr/local/python3 --with-ssl
make && make install
创建软链接
ln -s /usr/local/python3/bin/python3 /usr/local/bin/python3
ln -s /usr/local/python3/bin/pip3 /usr/local/bin/pip3
验证是否成功
python3 -V
pip3 -V
