Challenge exercise Add a non-animal actor to the simulation. For instance, you could introduce a Hunter class with the following properties. Hunters have no maximum age and neither feed nor breed. At each step of the simulation, a hunter moves to a random location anywhere in the field and fires a fixed number of shots into random target locations around the field. Any animal in one of the target locations is killed. Place just a small number of hunters in the field at the start of the simulation. Do the hunters remain in the simulation throughout, or do they ever disappear? If they do disappear, why might that be, and does that represent realistic behavior? What other classes required changing as a result of introducing hunters? Is there a need to introduce further decoupling to the classes?