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[MUSIC]
0:00
Hi there, Pythonistas, Megan here.
0:09
And in this practice session you'll
be testing your knowledge of
0:11
emulating built-in methods
inside of given classes.
0:15
On the screen here you can see I
have two classes one called Dog and
0:20
the other called Shelter.
0:24
And what we're going to do is
you're going to add a dunder
0:27
string method to Dog that
will return the pet's name.
0:31
You'll also add a dunder equals
method to class Dog that will
0:36
check if the two dogs names are the same.
0:41
So given two dogs names,
if they are the same name,
0:45
it should return that they are equal.
0:48
And then last, you're going to add
a dunder iter method to class shelter,
0:51
to iterate through
the animals in the list.
0:57
So let's take a look at the code
that I've already given you here.
1:01
For class Dog,
I've given you an init method.
1:05
And I've set a default value of the name
to be Maddie, which is my puppies name.
1:08
Feel free to change it or
remove it, completely up to you.
1:14
It just makes things a little
bit faster sometimes.
1:18
So then self.name =
name to set that value.
1:21
Inside of Shelter,
also given you an init method,
1:25
and I've given you a list of animals.
1:29
And then I've given you
a function called add_animal,
1:32
which adds animals to your animals list.
1:35
And then let's take
a look down here below.
1:39
I've created three dogs for
you, maddie, jethro, and luna.
1:42
So, you can see this one I didn't have to
pass in a name, cuz I'm using the default
1:47
and then I passed in these two names for
the two other dogs.
1:51
So I've given you three dogs.
1:54
I have created a shelter, which is
actually one of my favorite shelters.
1:56
And then I've added those three
animals to the shelter already.
2:00
And then down here at
the bottom I've created a loop.
2:06
So for pet in our shelter,
if the pet's name equals maddie,
2:09
which is the variable that
holds our maddie dog here,
2:16
then it's going to print out equal.
2:22
And it's going to print out the pet
itself which will be the pets name coming
2:26
from your dunder string, and this will be
coming from your dunder equals method.
2:31
And of course your for loop here
is coming from dunder iter method,
2:37
I kinda put all three in one.
2:41
And then of course,
if their name is not equal to maddie,
2:43
then it's going to print not equal,
and the pet as well.
2:47
So with everything completed when I
run the file, python pets.py, I should
2:51
get equal because the first pet in our
list is Maddie, which is equal to itself.
2:57
So that will give us equal.
3:04
And then the other two pets are not
named Maddie so I get not equal.
3:05
Jethro not equal, Luna.
3:09
Give it a try and see how you do.
3:13
Best of luck.
3:15
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