Hi,
Just a point - it's possible to contain the mouse and, in doing so, make it even more tempting to some snakes.
A nice tall flowerpot placed upside down with a hole in the top big enough for the snake + eaten mouse (you'd be amazed how many people don't think of that bit) with some mouse bedding in the bottom will make the mouse feel safe, keep it contained away from the snake until the snake decides to investigate and also mimic a rodent burrow with a nest at the end from the snakes point of view.
dr del