Debian: how can I replace bash using Python?

According to the accepted answer for this SO question: http://ift.tt/1BcfP7S, Python can make a great bash replacement.

My question then, is this: how do I go about seamlessly make the switch? I think the main thing to sort out to make such a switch would be: when starting a virtual terminal, call some Pythonic version of a terminal, rather than something like Bourne shell.

Does that make sense? If yes, how could I go about doing that?