Many a time, you might have come across situations where your existing Python interpreter gets loaded & messed up with too many unrelated libraries leading to cumbersome.
To avoid such situations, the Python community always suggests having a separate Virtual Environment for each task/project.
Ways of Creating a Virtual Environment:
1. Virtualenv
2. Pipenv (My favorite)
1. Prerequisites
Install pip
Usually, Python3 comes with pip preinstalled. If you get an error “pip command not found”, use the following command to install pip:
sudo easy_install pip
2. Virtualenv
A tool for creating isolated virtual Python environments.
Install virtualenv
Virtualenv is a tool to create isolated Python projects. You can think of it as a cleanroom, isolated from other versions of Python and libraries.
Enter this command into the terminal:
sudo pip install virtualenv
Start virtualenv
Navigate to where you want to store your code, e.g., navigate to your project folder for which you want to create a separate virtual environment.
Create a new directory
mkdir my_project && cd my_project
Now, inside my_project folder, create a new virtualenv
virtualenv venv
here ‘venv’ is the name of the virtual environment getting created
Activate virtualenv
source venv/bin/activate
Deactivate virtualenv
deactivate
Python Version on the Virtual Environment
python --version
Install Packages
- Create a ‘requirements.txt’ file
- Add the name of the Python packages you need to install in the virtual env (each package in separate lines)
- Run the below command
pip install -r requirements.txt
Check installed packages
pip list
3. Pipenv
Pipenv is a Python virtual environment management tool. This is a tool that combines virtual environments with package management. It creates a new virtual environment for each project and automatically installs the required packages from a Pipfile. It’s designed to simplify the process of managing dependencies for your projects and provides a simpler interface than virtualenv.
pip install pipenv
Once you’ve done that, you can effectively forget about pip since Pipenv essentially acts as a replacement.
virtualenv -p python3 .venvpipenv install
If .venv folder is not created/not found, then pipenv creates a virtual environment in the default location on your system. Now, two new files, the [Pipfile](https://github.com/pypa/pipfile) (which is meant to replace requirements.txt) and the Pipfile.lock (which enables deterministic builds) will get created.
pipenv shell
This will create a virtual environment using the .venv folder in your project folder.
pipenv check
This will scan your dependency graph for known security vulnerabilities!
pipenv lock -r
This will convert Pipfileand Pipfile.lock into a requirements.txt file very easily.
In this tutorial, we learned how Python virtual environments avoid conflicts between dependencies of different projects or system-wide. Also, we learned how to work on distinct projects with different dependencies by switching between these self-contained environments using the two simple but powerful methods.
Happy to share my personal experiences!
Resources
- https://towardsdatascience.com/manage-your-python-virtual-environment-with-conda-a0d2934d5195
- https://docs.pipenv.org/advanced/#configuration-with-environment-variables
