What version of Python is included in various current OSes
For my own curiosity, here is a rundown of what version of Python is in various current OS distributions, along with whether or not a version of Python 3 is available as an optional package.
(The version of Python is my best guess at what you get if you run
python' at a command line.)
|OS||Python version||Optional Python 3?|
|Solaris 10 update 8||2.4.4 (2.6 available in Blastwave)||No|
|Red Hat Enterprise 5
(and CentOS 5)
|2.4.3||No (it's not in EPEL)|
|Ubuntu 8.04 LTS||2.5.2||No|
|Debian 5.0 (Lenny)||2.5.2||No|
|Debian unstable||2.5.4||No (but there's a version in 'experimental')|
|Fedora 12||2.6.2||No (but it will be in Fedora 13)|
|FreeBSD 8.0||2.6.2 (I think)||Yes|
|Mac OS X 10.4.11 (Tiger)||2.3.5||no?|
|Mac OS X 10.5.8 (Leopard)||2.5.1||no?|
|Mac OS X 10.6 (Snow Leopard)||2.6.1||yes, apparently|
(I apologize if I have slighted your favorite OS or Linux distribution; this is the subset of things that I either have machines running or know how to check. Feel free to add data in the comments.)
I care about long term supported OSes like RHEL and Ubuntu LTS because those are what we run. The front runner short-term OSes at least show where the wind is blowing for their longer-term compatriots, so it's pretty sure that the next version of Ubuntu LTS will have Python 2.6.x (or better) and some version of Python 3, and it's likely that the next version of RHEL will have 2.6.x+ and Python 3 as well.
(Solaris 10 is unlikely to ever update its version of Python, because Solaris 10 pretty much never updates anything. And no one has any idea at this point if there will be a 'Solaris 11' and if so, what it will look like or have.)
My understanding is that you need Python 2.6 if you're even going to start developing for a future Python 3 migration. Obviously having an optional version of Python 3 is even better. The slow uptake of new Python 2.x versions (and the very slow addition of optional Python 3 packages) is one reason that I am not very sanguine about Python 3's chances of general adoption any time soon, or about plans to stop developing Python 2.x.