inheritance with parent class specialization

I'm sorry if I'm hard to understand, English is not my first language.

I'm trying to have a Puppy class derived from a specialize parent class, but without knowing which parent class it will inherit. And at the same time, give the Puppy class a set of abstract methods to implement.

from abc import ABC, abstractmethod


class DogSkillSet(ABC):
    @abstractmethod
    def bark(self):
        raise NotImplementedError

    @abstractmethod
    def chase(self):
        raise NotImplementedError

    @abstractmethod
    def fetch(self):
        raise NotImplementedError


class Dog:
    def __new__(cls, race, **kwargs):
        if race == 'sheperd':
            return GermanSheperd()
        elif race == 'rott':
            return Rottweiller()


class GermanSheperd:
    def __init__(self):
        self.race = "sheperd"


class Rottweiller:
    def __init__(self):
        self.race = "rott"


class Puppy(Dog, DogSkillSet):
    def __init__(self, race):
        super().__init__(race)

    def bark(self):
        print("small woof")

    def chase(self):
        print("stare into the air")

    def fetch(self):
        print("stare into the air")

    def play(self):
        print('playing')


if __name__ == '__main__':
    my_dog = Puppy('berger')
    my_dog.bark()

But the inheritance doesn't happen after the specialization. Could you tell me what I am doing wrong.

Your Dog.__new__ which is inherited by Puppy, returns instances of GermanShepherd or Rottweiler, neither of which inherit from DogSkillSet (or Dog for that matter)