How to Create and Activate a Python Virtual Environment

Install virtualenv

In some distribution, virtualenv is already installed. You could check whether your distribution has already included it by

$ virtual --version

If not, install virtualenv via pip

$ pip install virtualenv

or via apt-get

$ apt-get install python-virtualenv

Create Project Virtual Environment

Use virtualenv to create the project Python virtual environment

$ cd your_project_folder
$ virtualenv your_project

Activate Project Virtual Environment

$ source your_project/bin/activate

It activates your project virtual environment. You could verify it by either of the two methods below.
Your console changes to something like below

(your_project)user@hostname:~/your_project$

Or list the system PATH environment variable

$ echo $PATH

You should see your_project path in the printed information.

Deactivate virtualenv

If you want to switch to another virtual environment or simply quit the current virtual environment, you could deactivate your virtualenv by

(your_project)user@hostname:~/your_project$ deactivate
user@hostname:~/your_project$