pop up lighting / lighting

It is hard to know whether the light is on or off when you see into the bathroom or the storage from the outside.
I suggest this idea to solve this inconvenient problem.
The light in the room will be popped on by turing the doorknob.when you turn the doorknob from the outside ,the light will be on.In this case it will be easier to find the light switch.however,the light will be off when you turn the doorknob from the inside.