tag with inheritance

from typing import List


class Parent:
    tags: List[str]

    def __init__(self):
        tag = 'parent'
        try:
            self.tags.append(tag)
        except AttributeError:
            self.tags = list([tag])


class ChildA(Parent):
    def __init__(self):
        tag = 'child_a'
        try:
            self.tags.append(tag)
        except AttributeError:
            self.tags = list([tag])
        super().__init__()


class ChildB(Parent):
    def __init__(self):
        tag = 'child_b'
        try:
            self.tags.append(tag)
        except AttributeError:
            self.tags = list([tag])
        super().__init__()


class GrandChild(ChildA, ChildB):
    def __init__(self):
        super().__init__()


if __name__ == '__main__':
    test = GrandChild()
    print(test.tags)