安装pyenv

yum -y install gcc zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel gdbm-devel db4-devel libpcap-devel xz-devel git

git clone https://github.com/yyuu/pyenv.git /opt/app/.pyenv/
# 配置环境变量
echo ‘export PYENV_ROOT="/opt/app/.pyenv"‘ >> ~/.bash_profile
echo ‘export PATH="$PYENV_ROOT/bin:$PATH"‘ >> ~/.bash_profile
if command -v pyenv 1>/dev/null 2>&1; then
        eval "$(pyenv init --path)"
fi
source ~/.bash_profile
# 查看pyenv版本
pyenv -v

pyenv help
Usage: pyenv <command> [<args>]
Some useful pyenv commands are:
   commands    List all available pyenv commands
   exec        Run an executable with the selected Python version
   global      Set or show the global Python version(s)
   help        Display help for a command
   hooks       List hook scripts for a given pyenv command
   init        Configure the shell environment for pyenv
   install     Install a Python version using python-build
   local       Set or show the local application-specific Python version(s)
   prefix      Display prefix for a Python version
   rehash      Rehash pyenv shims (run this after installing executables)
   root        Display the root directory where versions and shims are kept
   shell       Set or show the shell-specific Python version
   shims       List existing pyenv shims
   uninstall   Uninstall a specific Python version
   version     Show the current Python version(s) and its origin
   --version   Display the version of pyenv
   version-file   Detect the file that sets the current pyenv version
   version-name   Show the current Python version
   version-origin   Explain how the current Python version is set
   versions    List all Python versions available to pyenv
   whence      List all Python versions that contain the given executable
   which       Display the full path to an executable

# 使用 pyenv install --list 查看可以安装的python版本，安装3.6.4版本
pyenv install 3.6.4
# 安装完成后目录所在
/opt/app/.pyenv/versions
# 查看可使用的版本，前面带*表示当前使用的版本
pyenv versions
# 查看当前使用的版本
pyenv version

# pyenv管理python版本的三个基础命令
pyenv global <version>
pyenv shelll <version>
pyenv local <version>
# 使用pyenv global <version>配置当前用户的系统使用的python版本
pyenv global 3.6.4
python -V