求大神解答，求求求求求

class Dog:
    def work(self):
        print('正在受训')
class ArmDog(Dog):
    def work(self):
        print('追击敌人')
class UntrainDog(Dog):
    pass
class DrugDog(Dog):
    def work(self):
        print('搜寻毒品')
class Person:
    def workWithDog(self,dog):
        self.dog=dog
        self.dog.work()
while True:
    d=input()
    if d == '军犬':
        d1=ArmDog()
        Person().workWithDog(d1)
    elif d == '缉毒犬':
        d2=DrugDog()
        Person().workWithDog(d2)
    elif d == '未受训的狗':
        d3=UntrainDog()
        Person().workWithDog(d3)
    else:
        break

class Dog:
    def __init__(self):
        pass
    def work(self):
        print('正在受训')
        
class ArmDog(Dog):
    def work(self):
        print('追击敌人')
        
class UntrainedDog(Dog):
    pass

class DrugDog(Dog):
    def work(self):
        print('搜寻毒品')
        
class Person:
    def __init__(self,dog):
        self.dog = dog    
    def workWithDog(self):
        self.dog.work()

if __name__=='__main__':
    a = input()
    if a=='军犬':
        dog = ArmDog()
        Person(dog).workWithDog()
    elif a=='缉毒犬':
        dog = DrugDog()
        Person(dog).workWithDog()
    elif a == '未受训的狗':
        dog = Dog()
        Person(dog).workWithDog()
    else:
        print('请输入“军犬”“缉毒犬”“未受训的狗”')