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Ok, now we'll start using dictionaries
for more interesting things.

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If you've got $8,000 to spare, you
could buy yourself a smart fridge.

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They keep track of the food in them, and
let you know what you can make for tea.

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We're going to use some Python dictionaries
to do something similar.

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We've created the data for you, so start by
downloading the contents.txt file, from the

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resources for this video.

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Once it downloads, open the file and copy
the entire contents to your clipboard.

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Back in IntelliJ, create a new
Python file called contents.py

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Paste in the code you've copied, and you'll have
the basic dictionaries that we're going to use.

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The first dictionary is called pantry, and
it contains the food and ingredients that

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we've got available.

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This is even better than an 8,000 dollar fridge,
because we're tracking things that a fridge

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wouldn't know about.

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You wouldn't normally keep
rice in a fridge, for example.

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It's also unlikely that you'd keep your spices
- cumin, paprika, etc - in the fridge.

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So we're going a step further
- we've got a smart pantry (smile).

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The dictionary contains the names
of the food items and ingredients.

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They're the keys, and the values
are how much of each one we've got.

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On line 2, you can see that
we've got 500 grammes of chicken.

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We've also got 2 lemons, on
line 3, and various spices.

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The oil, on line 8, is
measured in millilitres.

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If you're in America, you may have been thinking
that 450 fluid ounces is a lot of oil.

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450 ml is about 16 fluid ounces,
or roughly a pint.

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A bit less than 2 cups.

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Ok, the next dictionary contains
the ingredients for some recipes.

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The keys are the names of the meals - things
like Butter chicken, on line 24, and Chicken

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and chips, on line 41.

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The meals get easier to cook, as you
get further down the dictionary.

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We finish with Spam a la tin, on line 59.

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That's quite an easy meal to prepare - you
open the tin and dive in with a spoon.

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I mention that because this is the order that
we'll be presenting the meals, to start with.

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I'll then show you how to sort the keys in
a dictionary, so that we can present the meals

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in alphabetical order.

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But we'll start off with this order.

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Before we start using these dictionaries,
take a closer look at recipes.

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The keys are the name of each recipe, or meal.

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The values are lists.

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Although there are restrictions on what you
can use as a dictionary key - which I'll talk

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about soon - you can use any
Python object as a value.

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We're using lists here.

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You can see the value for Butter
Chicken on lines 25 to 39.

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You can store tuples in a dictionary,
or even other dictionaries.

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Dictionary values can be anything
that Python knows about.

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That's pretty cool, and lets us
do all sorts of useful things.

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But we're starting off quite simple here.

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Our values are lists - specifically, lists
of the ingredients that we need for each recipe.

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If we want, we could extend that to
also include the recipe instructions.

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But it's a bit early for that, so we'll stick
with just the list of ingredients.

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On line 25, the first ingredient for Butter
Chicken is chicken, unsurprisingly.

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chicken is a key in the pantry
dictionary, on line 2.

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Each of the items in the list, on lines 25
to 39, must exist in the pantry dictionary,

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if we're going to make Butter Chicken.

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Data that's organised like this is
very common - and incredibly useful.

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It's common to have something like a list,
that contains keys in a dictionary.

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You might also have one dictionary, whose
values are keys in another dictionary.

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That would be useful here, in fact.

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Our recipes are a bit useless, because they
don't specify how much chicken we need.

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We'll extend this data soon,
and address that problem.

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But we're starting off simple, until we've
seen how these dictionaries work together.

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Alright, that's our data.

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In the next video, we'll start to
make use of these two dictionaries.