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Friends here our concept is

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'destructor' of a Class. See already we know about

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'constructor'. A 'constructor' is a special method and that is

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called by default

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whenever you create an object from a class.

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So first, let me show you this. Already we know this.

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So let me define a class called 'Person',

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[no audio]

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then in that I am defining a method called 'init'. You know

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that is nothing but 'constructor' of your class, then 'print(

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"an object has been created".)'

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You know this method will execute by default whenever you

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create an object.

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from this class. Right. See that. I am creating an object called

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'per1', then let me write simply,

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[no audio]

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and let me run this and see the result. "an object has been created".

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That's it.

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And because of this advantage, right, we can define

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variables or we can call some methods by default in

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this initialization method.

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Let's say for my 'per1'

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I need to assign name and age.

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So for that, you don't need to write a separate method. Suppose

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if you don't have 'constructor' then suppose name and age,

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let me write 'name_age'. Then for this you have to pass

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your 'name' and 'age', right. And then you have to write

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'self.name=' some 'name', then 'self.age='

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some 'age', then simply write 'return None'.

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And to assign your 'name' and 'age' you need to call

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from 'per1' 'name_age' method, like

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in this way. So after creation of an object, 'per1.name_age', then

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you have to pass,

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suppose some name,

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[no audio]

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then let's say some age, in this way.

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[no audio]

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Right, but because of this advantage, you know by default

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initialization method is calling, that's why what I will do

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is instead of defining your name and age for your object,

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I will write the code here itself and I will delete this

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method. Now, I reduced one method to define my age, and I mean

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for my 'per1', or for my object, name and age.

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Right. Yeah, fine.

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[no audio]

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Now this initialization method is requiring two variables - name

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and age. Now, let me take them as arguments.

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[no audio]

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And now your 'self' method requires two arguments, right. See

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that, in the output error, name and age, 'missing 2 positional

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required arguments: 'name' and 'age'.'

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That's why while calling,

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I mean while creating an object, here itself you have to

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pass the arguments which are required for your

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[no audio]

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initialization method or 'constructor' method. That's it.

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[no audio]

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Right. That's fine.

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Now, just assumed that

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you've done your work with your objects,

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[no audio]

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then I don't want to waste my RAM memory,

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then I need to delete my objects from RAM.

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Then at the end, suppose you have to write deletion 'per1'

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object, or if you create any number of objects, that many

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number of objects

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you have to delete it.

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Right. That's fine.

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That's fine. You can delete it manually or explicitly by writing 'del', your

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object name. But in Python you don't need to delete objects.

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[no audio]

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Right. See that first thing, 'destructor'.

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Destructor is a method first of all, and that method will

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call when an object gets destroyed.

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But we don't need to delete an object. Python is having automatic

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garbage collection or garbage collector, that will manage

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memory automatically. See that. But to understand that whether it

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is deleting or not,

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there is a predefined 'destructor' method that is called

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'__del'.

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And be clear, you don't need to write this deletion method,

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and don't need to use in your codes, but for interview point

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of view you have to know what is the use of deletion method.

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[no audio]

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First let me write my code, "object has been deleted".

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[no audio]

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Let me write 'return', simply 'None'. Now see the output. Because

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of this object, I mean automatically this initialization method will call,

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and because of automatic garbage collector of your Python

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once if you've done your work, it will automatically delete.

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Whenever your 'per1' object is deleting from your memory,

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at that time just it will call automatically deletion method

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if you have inside of your code. If you don't have, no problem.

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And in this method we have this information that's why it is

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printing. So guys

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finally you have to know one thing, 'constructor' method will

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call by default whenever if you create an object, and deletion

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method or 'destructor' method will call by default whenever

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an object has been deleted from your memory by your Python,

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but not by you. Automatically you'll delete an object. At that time

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just to know that whether it is deleting,

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or not we are using 'deletion' method. That's it.

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Okay. But while writing your codes, you don't need to use

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this 'deletion' method. But if you use it's good. Right. But

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for interview point of view, it is important simply. Right.

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Okay guys, thank you for watching this simple video.

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[no audio]