Debian – Install newer & older versions of python on debian

debianpython

How can I install extra versions of python on Debian (jessie). On Ubuntu I can use the "deadsnakes" PPA which will give me any python version I want, with the version name in the command (e.g. python33 for python 3.3). This allows me to install them all beside each other. I can use virtualenvs to install specific python packages for specific versions without messing with the system packages. I maintain some python libraries, and they need to work on many versions of python. If I have the python binary installed, then tox will take care of using virtualenvs for each python version.

So what's the debian equivalent of Ubuntu's deadsnakes PPA?

UPDATE I want to install python: 2.6, 2.7, 3.3, 3.4 and 3.5.

Best Answer

Using the PPA

You can use the PPA on Debian. Pick an Ubuntu version that's from slightly before your Debian version, and it should have all the necessary libraries. For wheezy, the oneiric PPA seems ok (but it lacks more recent Python versions). For jessie, the trusty PPA should work.

To add a PPA on Debian, create a file /etc/apt/sources.list.d/deadsnakes.list containing

deb http://ppa.launchpad.net/fkrull/deadsnakes/ubuntu trusty main 
deb-src http://ppa.launchpad.net/fkrull/deadsnakes/ubuntu trusty main

Download the PPA signing key with

gpg --keyserver keyserver.ubuntu.com --recv-keys DB82666C

then add the key to the APT key database with

gpg --export DB82666C | sudo apt-key add -

Finally run apt-get update and install the desired packages.

If you can't get the PPA working for some reasons (maybe you can't find a version that works with the libraries you have), you can download the source and recompile them for your distribution.

Using a chrooted system

What I usually do to test compatibility with other versions is to run older or newer distributions in a chrooted system. For example, you could install various versions of Ubuntu with the Python versions you're interested in, or you could install trusty in a chroot and install the PPA there. For more information, see my schroot guide.

Related Solutions

Python – Using Different Versions on Linux

The recommended way of having multiple Python versions installed is to install each from source - they will happily coexist together. You can then use virtualenv with the appropriate interpreter to install the required dependencies (using pip or easy_install). The trick to easier installation of multiple interpreters from source is to use:

sudo make altinstall

instead of the more usual "sudo make install". This will add the version number to the executable (so you'd have python-2.5, python-2.6, python-3.2 etc) thus preventing any conflicts with the system version of Python.

Debian – How to install Python 3.x on Debian

I'm going to assume you've got Debian lenny and have your sourcelist geared towards the stable release which by default only has python2.5 (someone correct me?)

From a brief scan of their package tree, python3.1 exists in the Debian Sid (unstable) and Debian Squeeze (testing) tree. See Here

You can w-get directly from the links provided, but that's often messy as you'll need to resolve any dependencies yourself through a game of what don't I have? with the CLI.

If you're apt for switching your package tree to squeeze, you can change your /etc/apt/sources.list to match that of the squeeze tree. From there, you can aptitude update then aptitude install python and you should have python3.1 and all its dependencies in tow.