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[MUSIC]

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Hi there, Pythonistas, Megan here.

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And in this practice session you'll
be testing your knowledge of

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emulating built-in methods
inside of given classes.

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On the screen here you can see I
have two classes one called Dog and

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the other called Shelter.

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And what we're going to do is
you're going to add a dunder

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string method to Dog that
will return the pet's name.

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You'll also add a dunder equals
method to class Dog that will

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check if the two dogs names are the same.

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So given two dogs names,
if they are the same name,

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it should return that they are equal.

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And then last, you're going to add
a dunder iter method to class shelter,

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to iterate through
the animals in the list.

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So let's take a look at the code
that I've already given you here.

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For class Dog,
I've given you an init method.

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And I've set a default value of the name
to be Maddie, which is my puppies name.

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Feel free to change it or
remove it, completely up to you.

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It just makes things a little
bit faster sometimes.

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So then self.name =
name to set that value.

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Inside of Shelter,
also given you an init method,

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and I've given you a list of animals.

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And then I've given you
a function called add_animal,

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which adds animals to your animals list.

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And then let's take
a look down here below.

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I've created three dogs for
you, maddie, jethro, and luna.

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So, you can see this one I didn't have to
pass in a name, cuz I'm using the default

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and then I passed in these two names for
the two other dogs.

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So I've given you three dogs.

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I have created a shelter, which is
actually one of my favorite shelters.

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And then I've added those three
animals to the shelter already.

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And then down here at
the bottom I've created a loop.

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So for pet in our shelter,
if the pet's name equals maddie,

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which is the variable that
holds our maddie dog here,

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then it's going to print out equal.

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And it's going to print out the pet
itself which will be the pets name coming

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from your dunder string, and this will be
coming from your dunder equals method.

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And of course your for loop here
is coming from dunder iter method,

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I kinda put all three in one.

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And then of course,
if their name is not equal to maddie,

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then it's going to print not equal,
and the pet as well.

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So with everything completed when I
run the file, python pets.py, I should

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get equal because the first pet in our
list is Maddie, which is equal to itself.

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So that will give us equal.

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And then the other two pets are not
named Maddie so I get not equal.

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Jethro not equal, Luna.

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Give it a try and see how you do.

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Best of luck.