Solution to objects

gistfile1.py

""" Objects models file.

    Edit the class definitions to make the tests pass.
"""


class Dessert(object):

    def __init__(self, price, calories=None):
        self.price = price
        self.calories = calories

    def calories_per_dollar(self):
        if self.calories:
            return self.calories / self.price

    def is_a_cake(self):
        return False


class Cake(Dessert):
    price = 5
    calories = 200

    def __init__(self, kind):
        self.kind = kind

    def is_a_cake(self):
        return True


class Menu(object):

    def __init__(self, items):
        self.items = items

    def desserts(self):
        # Return only the items in self.items which are desserts
        desserts = []
        for item in self.items:
            if isinstance(item, Dessert):
                desserts.append(item)
        return desserts

    def cakes(self):
        # Return only the items in self.items which are desserts
        cakes = []
        for item in self.items:
            if item.is_a_cake():
                cakes.append(item)
        return cakes