upgrade.md

CentOS 6 升级Python 2.6到3.6

• 升级到 3.6

  • 查看版本

      $ python -V
    

  • 安装python 3.6

      $ wget https://www.python.org/ftp/python/3.6.1/Python-3.6.1.tar.xz 
      $ tar xvf Python-3.6.1.tar.xz
      $ cd ./Python-3.6.1 
      $ mkdir /usr/local/python3
      $ ./configure --prefix=/usr/local/python3
      $ make && make install
      //备份旧版本
      $ mv /usr/bin/python /usr/bin/python_old
      // 建立软链接
      $ ln -s /usr/local/python3/bin/python3 /usr/bin/python
      $ python -V
    

• 解决yum异常

  • yum报错

      $ yum search
      File "/usr/bin/yum", line 30
          except KeyboardInterrupt, e:
                                  ^
      SyntaxError: invalid syntax
    

  • 修改/usr/bin/yum

       vi /usr/bin/yum
      #!/usr/bin/python    改成：    #!/usr/bin/python_old
    

• pip报错

  • pip install报错

      pip install pymysql
      Traceback (most recent call last):
        File "/usr/local/python3/lib/python3.6/site-packages/pkg_resources/__init__.py", line 659, in _build_master
          ws.require(__requires__)
        File "/usr/local/python3/lib/python3.6/site-packages/pkg_resources/__init__.py", line 967, in require
          needed = self.resolve(parse_requirements(requirements))
        File "/usr/local/python3/lib/python3.6/site-packages/pkg_resources/__init__.py", line 858, in resolve
          raise VersionConflict(dist, req).with_context(dependent_req)
      pkg_resources.VersionConflict: (pip 19.1.1 (/usr/local/python3/lib/python3.6/site-packages), Requirement.parse('pip==7.1.0'))
    
      During handling of the above exception, another exception occurred:
    
      Traceback (most recent call last):
        File "/usr/bin/pip", line 5, in <module>
          from pkg_resources import load_entry_point
    

  • 修改pip命令

      $ ln -s /usr/local/python3/bin/pip3 /usr/bin/pip