https://blog.csdn.net/LJX_ahut/article/details/110450091

[root@localhost ~]#  curl -O https://www.python.org/ftp/python/3.6.8/Python-3.6.8.tgz

# 解压
[root@localhost ~]#  tar xzvf Python-3.6.8.tgz
# 使用yum安装必要的工具
[root@localhost ~]#   yum install yum-utils
# 构建python依赖环境
[root@localhost ~]#  yum-builddep python
# 进入文件夹
[root@localhost ~]# cd Python3.6.8
# 运行配置，默认安装位置为/usr/local/bin/,改变使用–prefix=/alternative/path，建议使用默认配置
[root@localhost ~]# ./configure
# 编译  
[root@localhost ~]#  make
# 安装
[root@localhost ~]#  make install

[root@localhost ~]# python3 --version
Python 3.6.8
[root@localhost ~]# whereis python
python: /usr/bin/python /usr/bin/python2.7 /usr/lib/python2.7 /usr/lib64/python2.7 
/etc/python /usr/local/bin/python3.6m /usr/local/bin/python3.6 /usr/local/bin/python3.6m-config 
/usr/local/bin/python3.6-config /usr/local/lib/python3.6 /usr/include/python2.7 /usr/share/man/man1/python.1.gz




# 进入 /usr/bin 目录
[root@localhost ~]# cd /usr/bin
# 删除指向python2 的软连接
[root@localhost ~]# rm -rf python
# 重新建立python3和pip3的软连接，此实例安装位置为/usr/local/bin/,如安装位置不同，请切换
[root@localhost ~]# ln -sv /usr/local/bin/python3   /usr/bin/python
[root@localhost ~]# ln -sv /usr/local/bin/pip3   /usr/bin/pip





[root@localhost ~]#  vim   /usr/bin/yum
# 把文件头部的解释器   #!/usr/bin/python   改成    #!/usr/bin/python2.7
[root@localhost ~]#  vim /usr/libexec/urlgrabber-ext-down
# 把文件头部的解释器   #!/usr/bin/python   改成    #!/usr/bin/python2.7
[root@localhost ~]#  vim /usr/bin/yum-config-manager
# 把文件头部的解释器   #!/usr/bin/python   改成    #!/usr/bin/python2.7