pyenv

1. what?

1.1. a Python version management tool

1.1.1. allow changing the global version of python

1.1.2. install multiple version of Pythons

1.1.3. set directory of project with specific Python version

1.1.4. create/manage virtualenv

2. how to use?

2.1. install

2.1.1. git clone git://github.com/yyuu/pyenv.git .pyenv

2.1.2. echo 'export PYENV_ROOT="$HOME/.pyenv"' >> ~/.bashrc

2.1.3. echo 'export PATH="$PYENV_ROOT/bin:$PATH"' >> ~/.bashrc

2.1.4. echo 'eval "$(pyenv init -)"' >> ~/.bashrc

2.1.5. source ~/.bashrc

2.2. install python by using pyenv

2.2.1. pyenv install 3.7.4

2.3. create new virtual env

2.3.1. pyenv virtualenv python_version(like pyenv virtualenv 3.6.0 name)