Beyond the Standard Library
Chapter 2: Virtual Environments
Activating your environment
Once you’ve created the virtual environment, you can activate it to ‘enter’ the environment.
To activate your environment on Linux/MacOS, you run a script called activate in my_env/bin as follows:
user@MACHINE:~/ai_project$ source my_env/bin/activate
(my_env) user@MACHINE:~/ai_project$
To activate your environment on Windows, you run a script called activate in my_env/Scripts as follows:
C:\Users\username\Documents\ai_project> .\my_env\Scripts\activate
(my_env) C:\Users\username\Documents\ai_project>
At this point, your console prompt should be prefixed with something like (my_env). This shows that you are currently using the version of Python in the my_env virtual environment.
When you run python or python3 with (my_env) displayed, you are running the version of Python in the my_env virtual environment. You can type which python (for Linux/MacOS) or where python (for Windows) to check which version you are using.
Leaving your environment
To deactivate a virtual environment, simply run deactivate. The (my_env) prefix will disappear, and you will go back to using your main version of Python.
(my_env) user@MACHINE:~/ai_project$ deactivate
user@MACHINE:~/ai_project$
Just activate the environment again as above when you need to use my_env.