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Great, you have your class that is now complete.

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Now let's say you want to create a class for a

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robotic arm. This class is actually a Robot, but

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with more functionalities, okay that are specific

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to robotic arm. So to create the robotic arm

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class, you will need to rewrite most of the Robot

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class code here, and there is a way to avoid doing

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that and directly create the robotic arm class on

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top of this Robot class. This is called

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inheritance. And let's see what this is and how to

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do that directly with a code example. So I'm going

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to create, I'm going to stay in my robot.py file

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here, and I'm going to create another class. So I

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go back to the line with zero indentation, class RoboticArm.

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Okay, and I'm going to do things a little

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bit different, I'm going to open parentheses and

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put Robot like this. This means that the RoboticArm.

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class will inherit from the Robot class. So

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basically, it will inherit from all the attributes

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and all the methods. So basically, if I just write

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this, and then if I do pass, which is basically

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the Python keyword, to do nothing, for the RoboticArm

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I can create a RoboticArm with the name,

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version number, it's also going to have an

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internal temperature, and I can call say_hi, init_hardware,

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and print_info, and that's going to work.

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Quite convenient, right? And we can also add more

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attributes and methods inside the RoboticArm

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class, which are this time specific to a RoboticArm,

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and maybe don't apply to any kind of robots.

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Okay, so I'm going to here, what am I going to do,

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I'm going to def __init__. So I'm going to create a

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constructor, and I'm going to do self name,

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version_number, and reach. So let's say that to

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initialize the RoboticArm, I need to give a name,

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version_number, so just like I did here, and a

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reach in millimeters, for example. So I have my

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constructor here with the parameters, and now what I'm

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going to do, in the constructor I'm going to call

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super open, closed parenthesis .__init__, okay, with

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name, version_number, and then I'm going to do

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self.reach is equal to reach. So what did I do

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here? Well, for any class, basically, you're going

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to create a constructor, okay. And here, if a

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class inherits from another class, what you can do

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inside the method is called a super function. And

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this super function is simply going to call a

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method that is from the, what we can call the

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mother class, okay. So if I do super().__init__,

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I'm going to call the constructor from the Robot

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class. So I don't need to write this another time

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inside this method. Okay. So I call the

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constructor from Robot, I initialize with the

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name, the version_number that I pass here, okay,

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initialize the temperature, and then I add self.reach

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is equal to reach, so I add another

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attributes, this time specific to RoboticArm.

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Okay, so that's it for the constructor. Now I'm

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going to add another method. For example, pick

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[Author typing]

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_object with, so self and then x and y

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coordinates. For example, let's just use a print

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Pick object on and then plus str(x), and then

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plus, let's add a comma here, str(y) plus, and

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then close the parentheses, okay. Pick objects on

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x and y. And I'm going to do def place_object,

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self, x, and y. Okay, and I'm going to do the same thing here.

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But instead of Pick, Place, so I can pick and place

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an object. That's very simplified for the example

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again. So here we have RoboticArm, we have all

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the attributes and all the methods of the Robot

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class, and we have some specific as you can see

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some specific attributes and specific methods,

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okay, which are specific to a RoboticArm and

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maybe don't apply to a drone or a submarine or any

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other kinds of robots. All right. So now I can use

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that class. So this is to the simple class, but I

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can use that class in my OOP example. What I can

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do is I can do from robots import RoboticArm. So

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let's keep my_robot here. Let's remove my_robot2,

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and I'm going to create my_robotic_arm is

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equal to RoboticArm, and I need to give it a

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name. So let's call it Bob. A version number,

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let's put 4, and reach, let's put 300, for

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example. And then what I can do, I can do so

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my_robotic_arm.print_info, okay. I don't have

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print_info here, I'm going to use the print_info

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from the Robot class. And I can use for example,

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my_robotic_arm.pick_objects, with let's say,

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three and four. And my_robotic_arm.place_objects,

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five and six. Let's see what it does. And

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as you can see, so we have first the text here,

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the print info of my robot, okay R2D2. And then

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we have the print info for, so Hello, my name is

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Bob, ready to help!. So Bob is the Robotic Arm, Version

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number: 4, okay, here. And then you can see Pick

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objects on three, four. Place objects on five,

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six, okay. And that pick_object is only available

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for the RoboticArm not for the normal Robot, and

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then well, so you have one level of inheritance.

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Now you can create another class if you want that

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inherits from the RoboticArm. Okay, you can

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create multiple levels of inheritance. And here are the

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different examples that you can inherit from

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Robot. Let's say you have a class of a Drone or a

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Mobile Base, or a Submarine, etc. Each of those

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classes can inherit from the Robot class. Alright,

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so to recap, that is how you can use the power of

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inheritance to create programming blocks on top of

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other programming blocks without reinventing the

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wheel every time.