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Everything in the Python program is an interaction between different entities.

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For example, we have libraries such as pandas.

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We have statements such as import.

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The return statement that if statement, the statement we have keywords such as the class keywords,

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def keywords.

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Then we have classes such as this block of code here.

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That's an entire class.

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Then we had instances.

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This year is an instance of a hotel class.

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That's another instance of.

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The hotel class as well.

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This string here is an instance of a string class.

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This other string is also an instance.

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Or for string class.

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Then we had.

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Functions.

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Which are these outside of classes?

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And then we have methods which are like functions, but they are inside classes.

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Such as this method here and that method there.

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So a Python program consists of interaction between things like functions and instances and methods.

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Even when you do things like ease the hello instance, the hello string instance equal to the high string

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instance.

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Even when you do that, what you're actually doing is you're calling a method.

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In this case it would be this method underscore, underscore, e, q, underscore, underscore.

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Hi.

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And you get the same output.

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Actually, you are not the one who are calling this method.

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The interpreter is calling this method on the background.

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So this is implicitly called and this here is known as syntactic sugar.

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You can think of syntactic sugar as simplified syntax so that you don't have to write that methods you

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can just do.

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Hello.

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Is equal to high.

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So that's more readable basically.

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Other examples would be one plus two.

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That would be the equivalent of one space dot.

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You have to use a space with numbers because it can be confused.

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Python doesn't doesn't know if it's a float or an integer if you don't provide space.

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So that would be add to and you get three.

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So when you do that, you're calling the ADD method.

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Actually now you can see a list of magic methods when you use there.

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For example, dear hello or just dear store.

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And you'll see the methods available for STR.

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Similarly, we can check for magic methods that our classes possess because STR is a class, right?

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Hotel is also a class.

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So let's copy this class in the python castle.

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You can either copy the entire class or.

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You can improve that class.

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But first, I'd like to remove all these.

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Let's just keep the definition of the classes here, save the script, and then from main, that's main

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to main to import the hotel class.

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Now hotel is available as a name in this Python session.

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And I can do Dear Hotel and you'll see that the hotel class has all these magic methods.

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Among the methods we will see.

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Underscore underscore e.

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Q So as you saw, that was the equivalent of this operator.

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So let's try to use this operator with two instances of the hotel class, right?

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Just like we used here, that operator with two instances of the string class.

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So hello is an instance of a string class.

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How is also an instance of string class?

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So let's do the same here.

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Let's create two instances.

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First, that would be hotel.

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You can either store them in variables or you can compare them directly.

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I'll store them in variables.

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So hotel.

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What do we need to provide?

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We need to provide the hotel ID.

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I'll just pass directly the value without mentioning the arguments you can do either way.

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So that would be.

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188 rate 188.

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I'll do another hotel instance and I'll provide the same.

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I'd actually.

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Still, these are treated as two different instances by Python.

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So if you do hotel, one is equal to hotel two, you get false.

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Why?

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Well, because these are basically treated as two different objects.

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And you can keep creating more hotel instances using the same ID, you can create ten of them and you

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can compare any of them, and all of them will be different from each other.

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That is not the case with things like strings, right?

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Hello is equal to hello and we get true.

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That is because the class string, when it was defined by some developers in the code developer team

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or the Python organization, they have overwritten the ECC methods.

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So this method and we can do the same so that when we compare hotel one and hotel two, if they have

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the same ID, we will return false.

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That should return false.

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So let's do that in our code.

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Let's overwrite that.

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E q methods.

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So we will change the behavior of that method.

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So let's go to the hotel class.

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Normally you add magic methods at the end, so after the last method, but make sure to be inside the

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class and write, define, underscore, underscore e Q The name has to be the same.

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Exactly the same.

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You'll see this gets this special color in Python.

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And now you want to specify how do you want this method to behave?

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So when do you want to treat two instances as being the same as being equal?

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Well, I think if self taught.

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Hotel.

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So this idea is.

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Equal to self dot hotel ID.

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Then we return true.

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Else we return false.

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Save the script.

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Then make sure to close this python session.

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You need to reopen a python session again.

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Otherwise you will be working on the old class which doesn't have the queue.

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Sorry, the queue method.

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So import in a new python session.

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Import from main to import hotel again.

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Create two instances hotel one with hotel.

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188.

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A hotel to Ace Hotel 188.

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Now, Hotel one is equal to Hotel two.

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Initially.

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We're going to get an error.

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And I'm glad this error happened because now you can understand a key concept here.

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So let's read the error.

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It says hotel IQ takes one positional argument, but two were given.

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So hotel IQ takes one positional arguments, which is true, right?

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It's only takes self a port.

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Two arguments were given here.

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What is the second argument that we've given to this IQ methods?

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Well, the second argument is the second instance, right.

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Because this here is equivalent of.

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Doing hotel.

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Actually, it's the equivalent of doing hotel.

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The class dot e, Q underscore underscore Hotel one, Hotel two.

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That's what we're doing.

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So we should reflect that syntax in here.

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So we should go there and add something like other.

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And then self should be updated to other here.

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So basically we are comparing.

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This current instance hotel one with this other instance which is passed as the second argument hotel

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to in this case.

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So hotel to that ID and so on.

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Right.

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So save that script.

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Close that Python console imports Again, you can use the upper arrow key to call previously executed

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statements.

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Import hotel creates a hotel.

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One instance creates a hotel, two instance with the upper arrow key.

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Compare the two.

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It should be this one and we get true.

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So now we can successfully compare two instances and evaluate them as true if they have the same idea.

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So this could be useful in your program.

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If you want to expand your program, for example, and you want to see if two hotel instances are the

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same.

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So to do that, you can just compare them like that, like you do with other.

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Instances.

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Types such as strings or numbers.

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So similarly, you can add more magic methods.

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You can override more magic methods here.

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Perhaps it makes sense to add to one hotel to another.

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So if that makes sense for your program, then you want to write exactly the behavior of what should

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happen when you add those two hotels together.

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So perhaps you want to access self that price.

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If you had a price instance variable, which we don't have in this case, but if you had one, you would

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do something like sell that price plus other that price.

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So you could.

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Add them at a total in a total variable, you could store them at other here and then return total.

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And then when you do hotel one plus hotel two, you would get the total price as.

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Output.

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So that would be a number.

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So I'm deleting that and that just to show you how it would be if you use the add magic method.

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So that was some magic about Python and you can try to experiment with more methods if you want to have

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some python fun.

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And I'll leave this lecture at this point.

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I hope this makes sense and it gives you some more advanced knowledge about how Python works, the inner

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works of Python.

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And yeah, I'll talk to you in the next videos.

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Thanks a lot for following.

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I'm very happy to have you here.

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See you.