1.安装依赖：
yum -y install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel gcc make epel-release
2.用wget下载python3的源码包：
wget https://www.python.org/ftp/python/3.6.8/Python-3.6.8.tar.xz
3.解压：
xz -d Python-3.6.8.tar.xz
tar -xf Python-3.6.8.tar
4.编译安装：
cd /root/Python-3.6.8
./configure prefix=/opt/server/python3
make && make install
5.添加软链接：
ln -s /opt/server/python3/bin/python3.6 /usr/bin/python3
6.查看是否安装成功：
python3 -V
7.安装pip3：
yum install -y python3-pip
python3 -m pip install --upgrade pip
