virtualenwrapper

install.sh

sudo easy_install pip

sudo pip install virtualenv
sudo pip install virtualenvwrapper

export WORKON_HOME=~/env

mkdir -p $WORKON_HOME

source /usr/local/bin/virtualenvwrapper.sh

# Say if you have Python 2.7.6 and you want to create virtual env with the existing one
mkvirtualenv venv1

# Say if you have Python 2.7.6 and you want to create virtual env with Python 3.6.3
# To do this you have to have Python 3.6.3
# This example tested on macOS High Sierra and can work
mkvirtualenv venv2 --python=/Library/Frameworks/Python.framework/Versions/3.6/bin/python3