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If all we could do with classes is set and

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use attributes, they wouldn't
be all that useful, would they?

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Like I mentioned before, though,

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we can give verbs to our
objects by creating methods.

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Now, don't get too worried about methods,
cuz I'll let you in on a secret.

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Methods are just functions
that belong to a class.

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So, if you can write a function,
you can write a method.

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They do have one little gotcha, though.

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So, let's get into Workspaces so
I can teach you all about them.

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So, I'm gonna simplify
things a little bit,

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I'm gonna leave out a couple
of things here at first.

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Methods in classes are the actions of
the instances of your class can do.

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For example, my Thief class might have
a pickpocket method that lets it try and

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snatch something out of
another person's pocket.

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Methods belong to the class, so
they're indented inside of it,

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just like attributes are.

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So, we'll say def pickpocket and
that'll take an argument self and

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then we'll return a bool of
random.randit between 0 and 1.

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And that means I

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need to import random.

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So, what's this self thing
that's going on here?

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What's that about?

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Well, methods are functions
that's belong to a class.

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Whenever they're used,

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however, they're used by an instance,
not by the actual class.

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Because of that, methods always
take at least one parameter,

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which represents the instance
that's using the method.

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Now, by convention that parameter's
always called self, but

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you can call it anything you
want in your own classes.

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But I highly recommend
you stick with self.

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Now, the neat thing here is you
don't give any arguments to self

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when you use the method.

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Let's try this out down
here in our console.

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So, Python from characters import Thief.

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And kenneth = Thief just like before,
right?

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So now, I can do kenneth.pickpocket().

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And just like any other function,
I have to call it with parenthesis.

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And since the method doesn't take any
arguments other than self I don't put

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anything inside of here.

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And I get back False, so
it randomly picked false.

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So, cool.

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Now, I don't usually like to show you
clunky ways of achieving something but

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I feel like this whole self thing
needs a little bit more explanation.

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Now, let's do the same method but

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we're going to do it in a slightly
different way, all right?

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So, if I tried to Thief.pickpocket().

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Then I get an error.

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I get this TypeError saying that
pickpocket is missing a required

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positional argument, self.

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Okay, so let's give it a self,
pickpocket, and

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I'm going to give it
an instance of the class.

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And this time I get False again.

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So, we just ran the exact same code, but

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this time we had to provide an argument
to pickpocket or it failed, right?

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Since we called it
directly from the class,

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we had to provide an instance
that it would be used by.

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So, let's add a little something to
the class to make this instance use

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more obvious.

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I' m gonna go ahead and exit and
them I'm gonna clear this screen.

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I'm gonna hop back up here to this.

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Okay, so inside pickpocket
let's add a new line here,

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print Called by, and
then let's fill that in with self.

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So, now our instance will print out who
it is that's trying to pickpocket someone

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else, okay?

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Maybe not the best approach for
a thief but

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we're here to learn not to
steal things from people.

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So, from characters import Thief,
kenneth = Thief.

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And now, let's do kenneth.pickpocket.

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Okay, called by characters.Thief
object at that address, and True.

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Cool, that time I succeeded, all right?

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So now, let's try our other method of it,
Thief.pickpocket().

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And we'll pass in the instance,
which is kenneth.

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And I get the same output,
the exact same output, right?

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Called by characters.Thief object
at 0x7f99b71edef0, all right?

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Exactly same memory address.

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So, the fact that we have the exact
same memory address shows us that it's

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using the exact same object for
calling the method both times.

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This self concept often trips
up early programmers, but

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practice makes perfect on it.

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And thankfully, Python will gripe at
you loudly if you forget to use self as

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a parameter if you forget
to call it on a method.

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All right, one more thing about self.

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We can always use self to talk about
the current instance, like in the method.

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So, let's check and

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make sure that our thief is sneaky before
we even attempt to pickpocket somebody.

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So, let's take out this print line.

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Cuz we don't need that.

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And let's say if self.sneaky,
and then we'll indent that.

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Otherwise, we'll return False, okay?

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So, if the instance's sneaky
attribute is set to True,

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then we'll try and pickpocket.

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Otherwise, we just always return a False.

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All right, so that's cool.

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Now let's give that a try.

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Come back down here.

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From characters import Thief.

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kenneth = Thief().

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And let's try this.

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So, kenneth.pickpocket().

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And we get false, and
if I run this another time or two I get,

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yeah there we go, True, False, whatever.

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Okay, so now let's make sure
that I am not sneaky, all right?

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I'm a clumsy non sneaky thief.

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And now, let's try kenneth.pickpocket().

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False, False, False,
False, False, all right?

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So, it's always False.

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I'm gonna get caught cuz I'm not sneaky.

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So, inside of a class's method,
self always refers to the instance.

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And I can use that to get to
the instance's attributes and

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even other methods.

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Let's try this whole method thing
out with a co-challenge or two.