.. _virtualenv-heading:

Virtualenv
=========================

Why Use Virtualenv?
-------------------------

You should use `Virtualenv <https://virtualenv.pypa.io/en/latest/>`_ because:

*   It allows you to install multiple versions of the same dependency.

*   If you have an operating system version of Python, it prevents you from changing its dependencies and potentially messing up your os.

How to Use Virtualenv
-----------------------------

Create your project folder, then a virtualenv within it::

    $ mkdir myproject
    $ cd myproject
    $ python3 -m venv .venv

Now, whenever you want to work on a project, you only have to activate the
corresponding environment.

.. tabs::

    .. group-tab:: OSX/Linux

        .. code-block:: text

            $ . .venv/bin/activate
            (venv) $

    .. group-tab:: Windows

        .. code-block:: text

            > .venv\scripts\activate
            (venv) >


You are now using your virtualenv (notice how the prompt of your shell has changed to show the active environment).

To install packages in the virtual environment::

    $ pip install click

And if you want to stop using the virtualenv, use the following command::

    $ deactivate

After doing this, the prompt of your shell should be as familiar as before.
