Question about Python upgrade on linux

[guandalino]

Hi, suppose I have python 2.6.4 installed from source and I want to
upgrade to 2.6.5. Python standard library is automatically upgraded at
2.6.5 as well, while 3rd party pure Python and extension modules in
site-packages don't. Is it safe to keep the old site-packages or is it
suggested to reinstall modules and/or recompile extensions using the
new Python?

And to upgrade from 2.6 to 2.7?

Thanks,
best regards.