I thought this would be fun. So, for kicks, I made a BBGW (BeagleBone Green Wireless) and a Sabertooth 2 x 12 connection via UART. I added a couple of batteries, e.g. one for the BBGW and one for the physical aspects (motor and Sabertooth).
I also used a Flask microframework from a pip install from Python. I did use pysabertooth along w/ a HTML page.
Um...yep. That is it. It just listens to commands and goes when I say go. It also stops.
P.S. The library, pysabertooth, can be found online at https://github.com/MomsFriendlyRobotCompany/pysabertooth . There is a MIT license and it shows that on the README file on the home page. This is my idea of their production from pysabertooth but on my terms: https://github.com/silver2row/sabertooth .