• ABC: Abstract Base Class
• Always use the ABC as base class for abstract classes
• Avoid using the ABCMeta to define an abstract class
• Use the ABC suffix if you want to determinate that the class is abstract
• Use ABC classes to create interfaces

✅ Do

class Building(ABC):
    pass

class BuildingABC(ABC):
    pass

❌ Don't

class Building:
    pass

class BuildingABC:
    pass

class IBuilding(ABC):
    pass

class Building(metaclass=ABCMeta):
    pass