How to Install Python on Ubuntu 18.04: A Comprehensive Guide

Introduction

Python is one of the most popular programming languages used in various fields, from web development to data science. If you're working on a project that requires Python, you might need to install it on your Ubuntu 18.04 system. This guide will walk you through the process of installing Python, upgrading it, and setting up a virtual environment, all in a systematic approach. For those interested in managing multiple Python versions, we will also discuss pyenv and conda as alternatives.

Installing Python on Ubuntu 18.04

Ubuntu 18.04 comes with Python 3 pre-installed. However, if you need a specific version or wish to verify the installation, follow the steps detailed below.

Step 1: Update the Package List

First, update your package list to get the latest information about available packages:

sudo apt update

Step 2: Install Python

Ubuntu 18.04 usually has Python 3 installed by default:

sudo apt install python3

Step 3: Verify the Installation

To confirm that Python is installed correctly, check the version:

python3 --version

Step 4: Install pip Python Package Installer

pip is the package manager for Python. Install it with the following command:

sudo apt install python3-pip

Step 5: Verify pip Installation

To ensure pip is installed, check its version:

pip3 --version

Installing Python with pyenv

pyenv is a tool that allows you to install and manage multiple versions of Python on a single system. It's particularly useful if you need to work with different projects requiring different Python versions.

Installing pyenv

To install pyenv, follow these steps:

Clone the pyenv repository to your home directory:

git clone ~

echo 'export PYENV_ROOT"$"' >> ~

echo 'export PATH"$PYENV_ROOT/bin:$PATH"' >> ~

echo 'eval "$(pyenv init -)"' >> ~

echo 'eval "$(pyenv init --path)"' >> ~

Open a new terminal session to load the changes.

Install the Python version you need:

pyenv install 3.8.0 (Replace 3.8.0 with the version you need)

Creating Isolated Python Environments with venv

If you want to work in isolated environments, you can use venv. This is particularly useful for setting up virtual environments for specific projects.

Creating a Virtual Environment

To create a virtual environment, navigate to your project directory and run:

python3 -m venv myenv

Replace myenv with your desired environment name. To activate it, use:

source myenv/bin/activate

When you're done, you can deactivate the virtual environment by typing:

deactivate

Conclusion

You now have Python and pip installed on your Ubuntu 18.04 system. You can start developing Python applications or managing packages as needed. If you have any further questions or need assistance with specific packages or projects, feel free to ask!

If you are doing some sort of data science, you might want to consider using the Anaconda Python comes with conda, a powerful package and environment manager, which allows you to create virtual environments of Python 2 or 3 easily.

For a visual walkthrough, check out this video guide on how to install Python 2 or 3 on Ubuntu 18.04.