Handle set like 40-034K that locks automatically?

I am looking for a mechanism like the 40-034K for an outside screen door to a pool area. I would like the mechanism to lock from the outside without having to lock it with the key. A pool service person comes in through the door to an enclosed pool area which has a locking screen door. Sometimes he forgets to lock it again once he leaves, so I was looking for a mechanism that was always locked from the outside and, thus, locks automatically when it is is closed.