Python3 與 Python2共存

1. 查看當前python版本

                   
                     python --version
                   
                 

2. 備份python

                   
                     which python
   mv /usr/bin/python /usr/bin/python.bak
                   
                 

3. 下載安裝更新python3

                   
                     wget https://www.python.org/ftp/python/3.6.2/Python-3.6.2.tar.xz
   tar -xvJf  Python-3.6.2.tar.xz
                   
                 

4. 安裝關聯程序，安裝編譯python3

                   
                     yum install -y zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel gcc make
   cd Python-3.6.2
   ./configure prefix=/usr/local/python3
   make && make install
   ln -s /usr/local/python3/bin/python3 /usr/bin/python
                   
                 

5. 查看python版本

                   
                     python --version
                   
                 

6. 修改相關執行程序python版本

                   
                     vi /usr/bin/yum
   把#! /usr/bin/python修改為#! /usr/bin/python2
   vi /usr/libexec/urlgrabber-ext-down 
   文件里面的#! /usr/bin/python 也要修改為#! /usr/bin/python2