Introducing natural predators for pythons like the king cobra might be a more scalable solution. It’s very hard to shoot all the members of an invasive species.
“We got a bit carried away,” said Moist. “We were a bit too creative in our thinking. We encouraged mongooses to breed in the posting boxes to keep down the snakes…” Lord Vetinari said nothing. “Er… which, admittedly, we introduced into the letter boxes to reduce the number of toads…” Lord Vetinari repeated himself. “Er… which, it’s true, staff put in the posting boxes to keep down the snails…” Lord Vetinari remained unvocal. “Er… These, I must in fairness point out, got into the boxes of their own accord, in order to eat the glue on the stamps,” said Moist, aware that he was beginning to burble