Light bulb
Create a world with a light bulb (Lights) and a method turn On Off that turns the light bulb on/off depending on whether it is already on/off. When the light bulb is on, its emissive color property has a value of yellow. When the light bulb is off, its emissive color is black. Write a Boolean function is Light On that returns true if the light bulb is on and false if it is off. When clicked, the light bulb should turn on/off.
