def generate(self):
# create a new planet
planet = Planet()
# populate with random humans and robots
for index in range(random.randint(1, 10)):
robot = Robot(f"Robot{index}")
planet.add(robot)
for index in range(random.randint(1, 10)):
human = Human(f"Human{index}")
planet.add(human)
# add to list of planets
self.planets.append(planet)
