Presumably once they ssh in they can install python in a virtualenv or do anything they want basically. I would imagine this would be only a bootstrap problem.
A few people have clarified what runs where, and you're ignoring them with an irrelevant and misleading point. To clarify, Python is not used on the slaves.
I wanted to know if "doesn't run on the target" means a bootstrap dependency only. After the target has been setup for configuration I don't see a reason why Python, Ruby or anything can't be installed in a sand-boxed environment.
