Homework: Classes and Attributes

Read sections 15.1, 15.2, 15.3, 15.4, 15.5, and 15.6 in the book and try out the code samples. You don't have to do any of the exercises.

Create a new class to model recipes:

class Recipe(object):
    """Models a recipe to make food."""
        

I can think of three attributes a recipe has: a name, a list of ingredients, and a list of instructions. (You can probably think of more.) Let's create a recipe and fill in these attributes.

>>> fake_chx_parm = Recipe()
>>> fake_chx_parm.name = "Microwave Chicken Parm"
>>> fake_chx_parm.ingredients = []
>>> fake_chx_parm.steps = []
>>> fake_chx_parm.ingredients.append("5 frozen chicken nuggets")
>>> fake_chx_parm.ingredients.append("1/3 cup pasta sauce")
>>> fake_chx_parm.ingredients.append("1 provolone slice")
>>> fake_chx_parm.steps.append("Microwave the frozen chicken nuggets in a small bowl for 1 minute, 25 seconds.")
>>> fake_chx_parm.steps.append("Pour the pasta sauce over one side of the heated nuggets.")
>>> fake_chx_parm.steps.append("Place the provolone slice over the pasta sauce.")
>>> fake_chx_parm.steps.append("Put everything back in the microwave for 25 more seconds, then enjoy!")
        

We could create another recipe:

>>> cup = Recipe()
>>> cup.name = "PB Cup"
>>> cup.ingredients = ["Peanut Butter Cup"]
>>> cup.steps = ["Unwrap it and eat."]
        

It's important to be able to see what these look like. Let's create a function to print out our recipes:

def print_recipe(recipe):
    """Nicely prints a Recipe object."""
    print("Recipe:", recipe.name)
    print() #Add a blank line
    print("Ingredients:")
    for ingredient in recipe.ingredients:
        print("  *", ingredient)
    print() #another blank line
    print("Steps:")
    for i in range(len(recipe.steps)):
        step = recipe.steps[i]
        print(" " + str(i) + ":", step)
        

Now try the code further above again to create recipes and call print_recipe on them! How does that look?