Creating a Virtual Environment

What is a Virtual Environment?

• As the name suggests, it is an environment virtually created to isolate the projects.

• This isolation helps to avoid discrepancies between the different versions of the libraries or packages as used by different projects in our system.

Why do we use a Virtual Environment?

• Say, we have installed Flask Framework of version 1.1 some time ago, and have built an app(say App A) based on that.

• Later, if we want to build an app(say App B) with the latest version of Flask, we need to upgrade Flask.

• Now that we have upgraded Flask on our system, we no longer will be able to run the App A smoothly, due to the differences in the versions.

• Virtual environments come to the rescue. If we create the two apps in 2 different virtual environments and install the corresponding packages or libraries in each virtual environment, both the apps run smoothly.

• For the above-mentioned reasons, it is a best practice to create any project in a virtual environment. We can create any number of virtual environments which is an incredible thing.

How to create and use a Virtual Environment?

• Creating a Virtual Environment:

  • We create a virtual environment with the name we mention using the following command: python3 -m venv <<your virtual environment name>>.

  Ex: python3 -m venv my_first_venv creates a virtual environment named my_first_venv.

• Activating a Virtual Environment:

  • After creating the virtual environment, we switch to that environment to create our project and install the dependencies inside that environment.

  • We switch to a virtual environment by using: source <<your virtual environment name>>/bin/activate

  Ex: source my_first_venv/bin/activate command switches to the virtual environment named my_first_venv.

• Deactivating a Virtual Environment:

  • To exit the environment, we just need to use the command: deactivate