#!/usr/bin/env python
class Animal():
    count = 0  # <1>

    def __init__(self, species, name, sound):
        self._species = species
        self._name = name
        self._sound = sound
        Animal.count += 1

    @property
    def species(self):
        return self._species

    @classmethod
    def kill(cls):
        cls.count -= 1

    @property
    def name(self):
        return self._name

    def make_sound(self):
        print(self._sound)

    @classmethod
    def remove(cls):
        cls.count -= 1  # <2>

    @classmethod
    def zoo_size(cls):  # <3>
        return cls.count


if __name__ == "__main__":
    leo = Animal("African lion", "Leo", "Roarrrrrrr")
    garfield = Animal("cat", "Garfield", "Meowwwww")
    felix = Animal("cat", "Felix", "Meowwwww")

    print(leo.name, "is a", leo.species, "--", end=' ')
    leo.make_sound()

    print(garfield.name, "is a", garfield.species, "--", end=' ')
    garfield.make_sound()

    print(felix.name, "is a", felix.species, "--", end=' ')
    felix.make_sound()
