Start up and exit python interpreter

Mac OS

• Type python3 in Terminal to start
• Type quit() or exit() to exit

Windows

• Type python in CMD to start
• Type quit() or exit() to exit

Locate where python is installed on your machine

• Mac OS

import os
import sys
os.path.dirname(sys.executable)

OR type where python3

• Windows

import os
import sys
os.path.dirname(sys.executable)

OR type where python

Create and activate virtual environment

• Windows

pip install virtualenv
virtualenv env --version

# navigate to project folder
cd Documents\GitHub\airflow

# create virtual environment
virtualenv venv_aiflow

# activate virtual environment
cd Documents\airflow\airflow\venv_airflow

Mac

create virtual environment using venv and the highest installed python

python3 -m venv env
source env/bin/activate

create virtual environment with a particular python version

python3.8 -m venv dbt_env
source dbt_env/bin/activate
python3 --version

create virtual environment using virtualenv

pip install virtualenv
virtualenv --version

# create project folder
cd Documents
mkdir airflow_env
virtualenv airflow_env -p python3

# activate virtual environment
source airflow_env/bin/activate

• https://virtualenv.pypa.io/en/latest/installation.html
• https://virtualenv.pypa.io/en/latest/

What if I don't have pip installed?

• you can use pipx to install virtualenv

# install pipx
python3 -m pip install --user pipx
python3 -m pipx ensurepath
pipx completions

# install virtualenv via pipx
pipx install virtualenv
virtualenv --help

• You can install pip using

curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py
python get-pip.py

• OR you can install pip via homebrew
  • this is recommended as it is likely you'll need pip for other installations

# install homebrew
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

# use brew to install pip and virtualenv
brew install brew-pip
brew install virtualenv

• https://brew.sh/
• https://formulae.brew.sh/formula/brew-pip

Install different python versions via homebrew

brew install [email protected]
brew install [email protected]
brew install [email protected]

python3 --version
python3.8 --version
python3.9 --version

• https://formulae.brew.sh/formula/[email protected]
• https://formulae.brew.sh/formula/[email protected]
• https://formulae.brew.sh/formula/[email protected]

References

• https://docs.python-guide.org/dev/virtualenvs/

• https://programwithus.com/learn/python/pip-virtualenv-windows

• https://pypi.org/project/pipx/

• https://virtualenv.pypa.io/en/latest/installation.html

• https://virtualenv.pypa.io/en/latest/

• https://realpython.com/python-virtual-environments-a-primer/

• https://realpython.com/courses/working-python-virtual-environments/