Introduction
Python is a flexible and versatile programming language that can be leveraged for many use cases, with strengths in scripting, automation, data analysis, machine learning, and back-end development. First published in 1991 with a name inspired by the British comedy group Monty Python, the development team wanted to make Python a language that was fun to use. Quick to set up and written in a relatively straightforward style with immediate feedback on errors, Python is a great choice for beginners and experienced developers alike. Python 3 is the most current version of the language and is considered to be the future of Python.
This tutorial will guide you through installing Python 3 on your local Linux machine and setting up a programming environment via the command line. This tutorial will explicitly cover the installation procedures for Ubuntu 18.04 or Ubuntu 20.04 or Ubuntu 22.04, but the general principles apply to any other distribution of Debian Linux.
Prerequisites :
- A system running Ubuntu 18.04 or Ubuntu 20.04 or Ubuntu 22.04
- A user account with sudo privileges
Step 1 — Setting Up Python 3
Ubuntu 18.04 or Ubuntu 20.04 or Ubuntu 22.04 ships with both Python 3 and Python 2 pre-installed. To make sure that our versions are up-to-date, let’s update and upgrade the system with the apt command to work with Ubuntu’s Advanced Packaging Tool:
sudo apt update
sudo apt -y upgrade
-y flag will confirm that we are agreeing that all items to be installed, but depending on your version of Linux, you may need to confirm additional prompts as your system updates and upgrades.
Once the process is complete, we can check the version of Python 3 that is installed in the system by typing:
python3 -V
You will receive output in the terminal window that will let you know the version number. The version number may vary, but it will be similar to this:
Output
Python 3.8.10
To manage software packages for Python, let’s install pip, a tool that will install and manage programming packages we may want to use in our development projects.
sudo apt install -y python3-pip
Python packages can be installed by typing:
pip3 install package_name
Here, package_name can refer to any Python package or library, such as Django for web development or NumPy for scientific computing. So, if you would like to install NumPy, you can do so with the command pip3 install numpy.
There are a few more packages and development tools to install to ensure that we have a robust setup for our programming environment:
sudo apt install -y build-essential libssl-dev libffi-dev python3-dev
Once Python is set up, and pip and other tools are installed, we can set up a virtual environment for our development projects.
Step 2 — Setting Up a Virtual Environment
Virtual environments enable you to have an isolated space on your server for Python projects, ensuring that each of your projects can have its own set of dependencies that won’t disrupt any of your other projects.
Setting up a programming environment provides greater control over Python projects and over how different versions of packages are handled. This is especially important when working with third-party packages.
You can set up as many Python programming environments as you would like. Each environment is basically a directory or folder on your server that has a few scripts in it to make it act as an environment.
While there are a few ways to achieve a programming environment in Python, we’ll be using the venv module here, which is part of the standard Python 3 library. Let’s install venv by typing:
sudo apt install -y python3-venv
mkdir , as in:
mkdir environments
Then navigate to the directory where you’ll store your programming environments:
cd environments
Once you are in the directory where you would like the environments to live, you can create an environment by running the following command:
python3 -m venv my_env
pyvenv sets up a new directory that contains a few items which we can view with the ls command:
ls my_env
Output
bin include lib lib64 pyvenv.cfg share
Together, these files work to make sure that your projects are isolated from the broader context of your server, so that system files and project files don’t mix. This is good practice for version control and to ensure that each of your projects has access to the particular packages that it needs. Python Wheels, a built-package format for Python that can speed up your software production by reducing the number of times you need to compile, will be in the Ubuntu 18.04 or Ubuntu 20.04 or Ubuntu 22.04 share directory.
To use this environment, you need to activate it, which you can achieve by typing the following command that calls the activate script:
source my_env/bin/activate
my_env . Depending on what version of Debian Linux you are running, your prefix may appear somewhat differently, but the name of your environment in parentheses should be the first thing you see on your line:
(my_env) qolko@ubuntu:~/environments$
my_env is currently active, meaning that when we create programs here they will use only this particular environment’s settings and packages. Note: Within the virtual environment, you can use the command python instead of python3 , and pip instead of pip3 if you would prefer. If you use Python 3 on your machine outside of an environment, you will need to use the python3 and pip3 commands exclusively.
After following these steps, your virtual environment is ready to use.
Step 3 — Creating a “Hello, World” Program
Now that we have our virtual environment set up, let’s create a traditional “Hello, World!” program. This will let us test our environment and provides us with the opportunity to become more familiar with Python if we aren’t already.
To do this, we’ll open up a command line text editor such as nano and create a new file:
(my_env) qolko@ubuntu:~/environments$ nano hello.py
print("Hello, World!")
Save the file and exit nano by pressing CTRL + X, Y, and then ENTER.
Once you exit out of the editor and return to your shell, you can run the program:
(my_env) qolko@ubuntu:~/environments$ python hello.py
hello.py program that you created should cause your terminal to produce the following output:
Output
Hello, World!
deactivate and you will return to your original directory. Conclusion
Congratulations! At this point you have a Python 3 programming environment set up on your Ubuntu Linux server and you can now begin a coding project!
