def num_object_mapping_factory():
    return {
        "Alien": 4,
        "Amidar": 2,
        "Assault": 4,
        "Asterix": 3,
        "BankHeist": 3,
        "BattleZone": 3,
        "Boxing": 2,
        "Breakout": 3,
        "ChopperCommand": 4,
        "CrazyClimber": 2,
        "DemonAttack": 4,
        "Frostbite": 3,
        "Gopher": 2,
        "Hero": 2,
        "Jamesbond": 4,
        "Kangaroo": 4,
        "Krull": 2,
        "KungFuMaster": 3,
        "MsPacman": 2,
        "Pong": 3,
        "PrivateEye": 3,
        "Qbert": 3,
        "RoadRunner": 4,
        "Seaquest": 3,
        "UpNDown": 3,
    }