class Pet:

    def __init__(self, n, a): # instance varibles (ie: state data, fields, properties)
        self.name = n
        self.age = a
        self.is_sleeping = False

    def set_is_sleeping(self, s): # setter is a mutator method
        self.is_sleeping = s

    def get_is_sleeping(self): # getter is fruitful
        if self.is_sleeping:
            return "Shhh, " + self.name + " is asleep."
        else:
            return self.name + " is awake!"

    def __str__(self):
        return self.name + " is " + str(self.age) + " years old."


class Dog(Pet):

    def __init__(self, name, age, b):
        # Pet.__init__(self, name, age) # works, but...
        super().__init__(name, age) # better to use super(); no need to send self
        self.breed = b

    def brush(self):
        print("Arf! Thanks for the dog brushing!")
    

class Fish(Pet):

    def __init__(self, name, age, sw):
        super().__init__(name, age)
        self.salt_water = sw

    def change_filter(self):
        print("Glug! Thanks for changing the filter.")

class Rock(Pet):

    def __init__(self, name, age, c):
        super().__init__(name, age)
        self.color = c

    def set_paint(self, c):
        self.color = c

    def __str__(self):
        return super().__str__() + "It's " + self.color

def main():

    my_dog = Dog("Chewki", 2, "Giant Chiuaua")
    print(my_dog)
    my_dog.brush()

if __name__ == "__main__":
    main()