CentOS7下安装Python3并保留Python2

1. 安装make编译指令的依赖环境

# 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 -y install zlib-