minimum python version for test suite?

[Tom Yu]

We are considering using Python in some portions of our test suite.
It appears that some operating systems ship with 2.5, but some
slightly older ones ship with 2.3.  Apparently certain desirable
language features are available on 2.5 that are not available on 2.3.

If you are inclined to run our test suite, what versions of Python do
you find to be readily available on their operating systems of choice?
Do you find that installing a version of Python that is newer than the
OS-provided version to be problematic?  What do you consider to be a
reasonable minimum required version of Python for our test suite?

Thanks.

-- 
Tom Yu
Development Team Leader
MIT Kerberos Consortium