How To Set Up a Virtual Python Environment (Linux)¶
virtualenv is a tool to create isolated Python environments. You can read more about it in the
Virtualenv documentation. This article provides a quick summary to help
you set up and use a virtual environment.
A Note About Python 3.6 and Ubuntu 16.04 LTS¶
If you’re running Ubuntu 16.04 LTS (or and earlier version), Python 3.5 is likely installed by default. Don’t remove it! To get Python 3.6, follow the instructions in this section.
Add the PPA¶
Run the following command to add the Python 3.6 PPA.
sudo add-apt-repository ppa:jonathonf/python-3.6
Check for Updates and Install¶
Check for updates and install Python 3.6 via the following commands.
sudo apt-get update
sudo apt-get install python3.6
Now you have three Python version, use python to run version 2.7, python3 for version 3.5, and python3.6
for version 3.6.
For more information on this subject, check out Ji m’s article How to Install Python 3.6.1 in Ubuntu 16.04 LTS.
Create a Virtual Python Environment¶
cd to your project directory and run virtualenv to create the new virtual environment.
The following commands will create a new virtual environment under my-project/my-venv.
cd my-project
virtualenv --python python3.6 venv
Activate the Environment¶
Now that we have a virtual environment, we need to activate it.
source venv/bin/activate
After you activate the environment, your command prompt will be modified to reflect the change.
Add Libraries and Create a requirements.txt File¶
After you activate the virtual environment, you can add packages to it using pip. You can also create a description
of your dependencies using pip.
The following command creates a file called requirements.txt that enumerates the installed packages.
pip freeze > requirements.txt
This file can then be used by collaborators to update virtual environments using the following command.
pip install -r requirements.txt
Deactivate the Environment¶
To return to normal system settings, use the deactivate command.
deactivate
After you issue this command, you’ll notice that the command prompt returns to normal.
Acknowledgments¶
Much of this article is taken from The Hitchhiker’s Guide to Python. Go buy a copy right now.