The consesus is to keep them separate. Ball pythons, like most reptiles, lead solitary lives and will get easily stressed if they have to share space with another animal. Although they have been known to eat their cagemates, it is not very common. However, they are more likely to go off feed because of stress.

Also, if one gets sick for whatever reason, it might be difficult to determine which snake is sick (runny stool) or they could easily transmit the illness to the other snakes.

You'll be doing your snakes a big favor if you would separate them into their own enclosures.