정보처리기사 실기 Python - 클래스와 매직 메서드 기출문제 #331

다음 Python 코드의 실행 결과를 쓰시오.

Python
class Meta(type):
    def __new__(cls, name, bases, dct):
        if len(bases) > 1:
            dct['priority'] = sum(getattr(base, 'priority', 0) for base in bases)
        else:
            dct['priority'] = 1
        return super().__new__(cls, name, bases, dct)

class A(metaclass=Meta):
    value = 10

class B(metaclass=Meta):
    value = 20

class C(A, B, metaclass=Meta):
    pass

class D(C, metaclass=Meta):
    pass

print(A.priority)
print(B.priority)
print(C.priority)
print(D.priority)