brew install pyenv-virtualenv
eval "$(pyenv init -)"
eval "$(pyenv virtualenv-init -)"
pyenv virtualenv 3.4.8 env
This sets up the virtual env in directory /Users/username/.pyenv/versions/3.4.8/envs/
pyenv activate env
python
Python 3.4.8 (default, May 3 2018, 16:39:36)
[GCC 4.2.1 Compatible Apple LLVM 9.0.0 (clang-900.0.39.2)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> quit()
pyenv deactivate