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One of the fundamental concepts of OOP object oriented programming

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is something known as encapsulation,

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which basically refers to keeping some sort of data

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private so that it can only be accessed or modified

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in certain ways.

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Now,

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this is very useful in cybersecurity because it

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allows us to protect sensitive data like passwords.

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OK?

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So

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as an example, we could write or create a class and objects

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that will store a user's password privately

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and then only provide a way to check if the input password is actually correct.

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So

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let me show you how we can encapsulate data using OOP.

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I'm going to keep the exact same class. OK. So class user,

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however, I'm going to change the attributive role to password.

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OK?

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And then obviously in here, I'm going to change self dot role

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to password

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and then this is gonna be equal to

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a password

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as well.

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However,

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the one way to tell Python that, hey,

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this particular attribute we want it to be private.

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This is in public information, this is private only to the user

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and we can do that by going over here

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in front of the P A password and then add in

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a double underscores.

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So this right here, the double underscores will indicate to Python that, hey,

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this is a private attribute. We want to encapsulate

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the information here.

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So

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let's now create a method

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which we can use to check whether or not

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the input provided by the user

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actually matches the real password for that user. So what I'm gonna do right now is

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I am going to define our method and let's call it authenticate. Ok.

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So define authenticate.

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And now in brackets,

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I'm gonna go with self

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and

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password.

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Ok.

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And we're doing this because self here is going to refer to the user whose

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password we actually want to check and

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then the password itself that we're checking.

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Ok.

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And now this is the key

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we would have to return.

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And now self dot

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underscore underscore

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password

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will be now equal to password. So

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we want to check

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if the password that's stored for the user is going to be

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the same as the password that was provided as an input.

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That's what this will do right here. Line eight.

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So if the password matches

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line eight will return true.

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But if there isn't a match, it's going to return false. Ok. So now

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we need to create our user objects

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and make sure that of course, whenever you're creating user objects,

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the intention is outside, it should be on the same intention as the class itself.

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Ok? Don't

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do it inside

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the class, but outside it has to match. So over here,

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I'm not gonna say

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user

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equals

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and now user,

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so let's say we need to provide a username. Uh Let's just go with guest.

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Ok, let's just go with guest,

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something very simple guest.

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And now for the password,

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I'm gonna go with capital S and then say sword fish, 123.

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Ok.

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So this is the password we've created for our user guest. Ok.

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Fine. Now

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let us try to authenticate the user by using different passwords. Ok.

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So

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let's try

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using the right password and then the wrong password. Ok. So

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how are we going to call our method?

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I'm gonna say print.

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And now in brackets,

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user

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dot

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authenticate.

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So we're calling the method right now to authenticate our user.

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And in brackets

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we want to provide the password we want to check. So

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the password in here right now, let me go with the right one is gonna be the same sword

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uh fish, 123,

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right?

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And then

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brackets. Ok,

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if I were on

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the program right now

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and oh,

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line 12, there's an error message. Oh, we should have an extra bracket in here.

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Sorry about that. Let me try it again

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and there you go. So now it says true because

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the password here,

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South Fish 123 is the same as the actual password that we've given to the user.

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Now, what I'm gonna do is I'm going to simply copy this line,

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OK, copy

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paste.

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And now let us try using a different password. So

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I'm just gonna go capital AB C 123

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and OK, that's it. So let me go ahead right now,

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we run the program again

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and now you can see that it is false because our method

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has checked AB C 123 is not equal to saltfish 123.

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So

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this is how we, we can encapsulate

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data

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using the object oriented programming.

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All we really have to do to indicate that a particular attribute is private,

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that we want to encapsulate

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is to have the double underscores

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in front of the actual attribute name. So

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that's it. Thank you for watching the video. I will see you in the next class.