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You now have a class with attributes,
a constructor and methods. Great!

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But this is just a structure
inside your program.

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If you run your code now like
this, well nothing is going to happen.

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So actually let's do that.
Let's do run and code.

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So, for example.
Well, this works but we have nothing.

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If I add, let's say I add here print,
let's say test, with zero indentation,

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I run it and I see
tests. So the test is

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executed but the class,
well nothing happened.

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So just as we have seen with a function,
well a function is just a bunch of code

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that you need to call in your program.
Otherwise it won't do anything.

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And this is the same for classes.
We need to create an object,

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also called an instance of the class,
so we can use the class functionalities.

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So let's actually do
this. I'm going to create

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an object here and I'm
going to call it myRobot

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is equal to robot, like this, and I open
the parentheses. And as you can see,

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so I have the suggestions
from PyCharm, so

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these, those here are
actually the parameters

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from the constructor here. So I need to
provide a name and a version number.

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So let's say our robot is named
R2D2 and the version number is,

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so here, well for the
version number you

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could use an integer,
float, string, whatever,

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and I'm just going to keep it very simple
and say this is the version 2 of the robot.

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So now I have my robot. So to create an
object, you call the constructor simply by,

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as you can see, writing
the name of the class and

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then parentheses. And if
there are any parameters

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here after self, you then need to provide
the parameters, so name and version number.

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What's going to happen
is that the name here, this

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is going to be a local
variable that is going to

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be assigned in the self
name, so in the attribute

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of the class and the
same for version number.

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So after we call this, this is going to be
self.name, this is going to be self.version

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number in the class.
And now what I can do, so

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here it's not going to
do anything, just create

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the robot with the
constructor and then what

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I can do, for example,
is my robot.sayI,

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okay, and then my robot.init_hardware
and then my robot.print_info.

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Okay, so as you can
see here, so the self, the

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first parameter is
actually not something that

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you have to add here,
the self refers to the object,

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so if you have this, it
means you have to call

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the method directly
from the object. So my

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robot.sayHi, it's going
simply to call this and pass

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the my robot object as
the self here, as simple

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as that. And then if you
have any other parameter,

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you call the parameter, but otherwise
that's it. I'm going to remove the test.

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So I create an object
and then I call the

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different functions or
the different methods.

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And then I can also
get access, so let's say

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print, I can get also
access to my robot,

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for example, dot, let's
say name. And so you can

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get access of the
attributes, okay, of the class

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also directly with my robot.name. Let's
run this now and let's see what we have.

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So we first create the
robot and then you can

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see sayHi is going to
say hello, my name is

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R2D2 ready to help.
Actually, I'm just going

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to add this here. And
then init hardware, okay,

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because we call init
hardware method. And then

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you can see we call
print_info, which is going to

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call sayHi another time,
so hello again. And then

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version number
temperature, which is from the

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print_info method.
And then, well, print my

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robot.name, which is going
to print R2D2, which is the

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attribute of the class
directly. Okay, nice. Now

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we have an object
created from the robot class.

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But actually, we can create
as many objects as we

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want from the class, okay.
Just as when you create

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a function, you can
just call it as many times

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as you want here. I'm
going to create another

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robot. Let's say my robot2,
okay. And then my robot2

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is going to be robot
also. So the constructor,

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and I'm going to give a
different name. Let's say

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C3PO, and this is going
to be version one of the

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robot. And I'm going to
remove that and remove

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that. And I'm simply going
to do my robot.print_info

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and my robot2.print_info.
Okay, so I call the

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same method from two
different objects, which have

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two different sets of
attributes. Okay, I run

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this. And you can see,
hello, my name is R2D2,

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version number two,
temperature 25. And then

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my name is C3PO and
version number one. Okay,

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so here we have two
complete independent and

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different objects, okay,
using the same class,

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the same blueprint,
but that have a different

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set of attributes, okay.
And you can use them

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independently. So to
recap, in order to create an

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object from a class, you
need to write the name

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of the class first to
call the constructor

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and pass the required
parameters to initialize

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attributes. Then from
that object, you can call

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the class methods. You
can also create multiple

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objects from the same
class. And each object will

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have its own internal mechanism and
attributes independent from the other objects.