Obviously if I had a cat I'd not care if it shat in other peoples' gardens as that seems to be part of the mentality of cat ownership, but if I lived next to a python I'd probably make sure it didn't wonder too far.
BTW, is it not a bit mean to keep a creature that never comes into contact with one of it's own kind? Does it not need a bit of like minded company – or just something to shag? Or do owners of snakes take them to meet up somewhere for a bit of company?