Install Python-3.1.2 For Linux

python 下载地址：

http://xiazai.zol.com.cn/detail/33/320958.shtml

1: 解压

bunzip2 Python3.1.2.tar.bz2

tar -xvf Python3.1.2.tar

2：安装到指定目录

sudo mkdir /usr/local/python3

cd Python-3.1.2/

./configure –prefix=/usr/local/python3

make & make install

3:查看版本

python

Python 2.7.6 (default, Mar 22 2014, 22:59:56)
[GCC 4.8.2] on linux2
Type “help”, “copyright”, “credits” or “license” for more information.
（我本机自带了python2.7.6而此时并没覆盖老版本）

4：替换原有链接

mv /usr/bin/python /usr/bin/python_2.7.6

/usr/local/python3/bin/python3 /usr/bin/python

5:查看版本

python

Python 3.1.2 (r312:79147, Dec 26 2017, 10:54:26)
[GCC 4.8.2] on linux3
Type “help”, “copyright”, “credits” or “license” for more information.

6：切换版本

/usr/bin/python_2.7.6

进入Python 2.7.6版本
如果嫌麻烦可以在$HOME/.bashrc 中添加一行
alias python2.7.6 = ‘/usr/bin/python_2.7.6’
保存并退出
source ~/.bashrc
之后输入python2.7.6即可进行版本切换