Understanding the Need for Python 2.7 in Ubuntu 20.04
While Ubuntu 20.04 comes with Python 3 as the default version, certain applications and legacy systems still rely on Python 2.7. Despite Python 2 reaching its end of life, there are scenarios where developers and system administrators need to install it for compatibility reasons. This guide will walk you through the process of installing Python 2.7 on Ubuntu 20.04 and setting up the environment for its use.
Preparing Ubuntu 20.04 for Python 2.7 Installation
Before proceeding with the installation of Python 2.7, it’s important to update the package list and install any available updates to ensure compatibility and security.
sudo apt update
sudo apt upgrade
Once the system is updated, you can proceed to install the necessary dependencies that will be required for compiling Python 2.7 from source.
sudo apt install -y build-essential libssl-dev libncurses5-dev libsqlite3-dev libreadline-dev libtk8.6 libgdm-dev libdb4o-cil-dev libpcap-dev
Downloading Python 2.7 Source Code
The next step is to download the Python 2.7 source code from the official Python website. It’s recommended to download the latest 2.7.x version to ensure you have the most recent security patches.
wget https://www.python.org/ftp/python/2.7.x/Python-2.7.x.tgz
tar -xvf Python-2.7.x.tgz
cd Python-2.7.x
Replace 2.7.x with the actual version number you are downloading.
Compiling Python 2.7
With the source code downloaded, the next step is to compile Python 2.7. This process can take some time, depending on your system’s performance.
./configure --enable-optimizations
make -j 8
The -j 8 flag tells the make command to use 8 cores for compilation, which speeds up the process. Adjust this number according to the number of cores your processor has.
Installing Python 2.7
After compiling the source code, you can now install Python 2.7 onto your system.
sudo make altinstall
Using altinstall instead of install prevents overwriting the default Python 3 installation.
Verifying Python 2.7 Installation
To verify that Python 2.7 has been installed correctly, you can check its version using the following command:
python2.7 --version
This should output the version of Python 2.7 that you have installed.
Setting Up a Virtual Environment for Python 2.7
Using a virtual environment is a best practice when working with Python projects. It allows you to manage dependencies and Python versions on a per-project basis.
sudo apt install -y python-virtualenv
virtualenv --python=python2.7 my-python-2.7-env
source my-python-2.7-env/bin/activate
This will create a new virtual environment named my-python-2.7-env and activate it.
Managing Python 2.7 Packages with pip
Python 2.7 comes with an older version of pip. To ensure you have the latest version, you should upgrade it immediately after installation.
curl https://bootstrap.pypa.io/pip/2.7/get-pip.py --output get-pip.py
sudo python2.7 get-pip.py
With pip installed, you can now manage Python 2.7 packages within your virtual environment or globally.
FAQ Section
Why do I need to install Python 2.7 when it’s no longer supported?
Some legacy applications and systems still require Python 2.7. While it’s not recommended for new projects, installing it can be necessary for maintaining and running older software.
Can I have both Python 2.7 and Python 3 installed on the same system?
Yes, you can have both versions installed. Using altinstall ensures that the default Python 3 installation is not overwritten.
How do I switch between Python 2.7 and Python 3 on my system?
You can specify the Python version by using python2.7 or python3 when running scripts or installing packages with pip.
Is it safe to use Python 2.7 for new projects?
No, it’s not recommended to use Python 2.7 for new projects as it is no longer supported and does not receive security updates.
How can I ensure that my Python 2.7 installation is secure?
Always download the latest 2.7.x version for security patches and consider using a virtual environment to isolate your Python 2.7 project.
