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Now that we have the structure of the class
with the constructor and the attributes,

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let's implement the
methods of the class or in

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other words, the
functionalities of the class.

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And to create a method,
well, it's almost the same

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thing as to create a function
like you did previously,

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and we have already actually our
first method, which is the constructor.

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Now we can add any number
of methods we want in the class,

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so still with the indentation to stay
inside of the class, and then def,

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and then I want to
implement the sayHi method.

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And as you can see, so this
is a functionality of PyCharm,

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whenever I create a
function or a method inside

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a class, I automatically
get the self parameter.

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If you don't get it, you simply write it.

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So self and we don't
want any other parameter.

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So as you can see, the first
parameter of any method would be self.

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Okay, so we have a reference to
the objects we are currently using.

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So the method is really linked to
the object and to the class robot.

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It's not just a function you
can call from anywhere.

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This is a specific function
that is directly linked to robot

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and you can only call it in
relation to the robot class.

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So sayHi, let's say we want to do so print.

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Hello, my name is, and
then let's do self.name.

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So as you can see with the self
keyword here, I can use self.name.

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And because I have created
self.name, this is going to work here,

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okay, because I have
initialized the variable or the

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attributes, okay, and then I
can use it in any other method.

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Okay, and then plus, let's
go back to a new line here.

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Let's do ready to help.

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Okay, so that's the sayHi method.

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And then I'm going to come back.

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So come back to the same
indentation here and do def init hardware.

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So again, we just need self.

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I'm not going to add any other parameter.

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Okay, colon.

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And actually, it's better if I end
the print with a parenthesis here.

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And here, because this is just an example,
I'm going to do print init hardware.

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Okay, just going to use a print.

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Okay, in real life, you
would actually implement

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this method to init
the real hardware here.

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We don't have any
hardware, just an example.

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So the point is to understand
how OP, so let's use a print here.

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So when we call that
method, we can see that

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we have actually
called it and that it works.

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And then I'm going to create
another one, def, let's say print info.

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Okay, again, with self, I don't
need any other parameter.

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And what I'm going to do here
is I'm going to print all the info,

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okay, which is the name, the version
number, and internal temperature.

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So I'm going first to do self.sayHi.

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Okay, as you can see, I
can directly call the method

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of the class from another
method of the class.

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Okay, and to do that,
I simply do self.sayHi.

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Okay, if I just call sayHi,
it's not going to work

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because the function
sayHi doesn't exist globally.

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But the method sayHi
exists inside the class robot.

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So if I do self. I can get access to the
different methods and attributes here.

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Okay, so you can see how to call
the method from another method.

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And then let's say print.

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So version number plus self version
number, I'm going to cast this as a string,

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because this is probably
going to be an integer flow.

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That can be a string, but we don't know.

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Okay, the name here is probably going
to be a string, so I don't need to cast it.

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But here, let's take some precaution.

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And then print temperature plus, and
then the same self internal temperature.

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Okay, so in this method,
you can see we call

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another method and we
use the different attributes.

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Okay, so self and the attributes.

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If you want, you can
also modify the attributes.

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Okay, you just do self version number
is equal to, and then you just change it.

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Okay, that's not a problem.

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So now we have a constructor,
we have three attributes,

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and we also have three
methods inside the class.

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All right, we have
successfully written all the

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functionalities of the class
inside different methods.

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And now let's go to the next step.