It won't be good for the snake--ball pythons don't exactly enjoy being fully exposed out in the open. It would be the worst day of his life.
Phobic individuals will freak out, and probably write to their senators.
A dog may decide to try to have your snake for lunch. After all, people bring their dogs to areas where dogs are allowed when they feel their dog can handle being around other dogs, and around people. They don't necessarily expect their dog not to chase squirrels, and it would never occur to them to test how their dog handles being confronted with a snake.
Bad idea.
