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We now move to operator overload and.

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But before starting with that, you'll have to note that all the python variables like strings, lists,

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dictionaries

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are all classes.

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We could take a simple example on the strings.

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Let's do a help train.

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See, this is actually the string class which is used python.

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Yeah.

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We have some method defined so I could see.

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So trains are actually classes, at least for you, not least.

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See, you have something like that.

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They.

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There we go.

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If we have two strings, this string one and we call it ABC.

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No, we have an in the string string too.

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We call it X, Y, Z.

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Let's print out string one plus string.

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So so we see how we combine this by simply doing what we just the year.

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Now if we define some of the variables, the variable E, we'll call it three and then variable B we

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call it for print is out.

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We have a plus.

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B, you see that in Python.

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Although with the know with different kinds of variables, we see that for this same addition operator,

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we are able to treat this two operations differently.

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Now let's modify this slightly.

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Suppose we have this call instead.

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So we have string one

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and string.

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So let's run that.

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You see that we have the same output we had when we just did the string, one plus string.

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So let's come back to the string.

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Help the search for ADD.

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Okay, now that we go, we see that this string class actually has this ADD method and this method is

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defined such that we have the current object so we see a self.

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Plus the value we pass in.

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And that's why.

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Plus the object we pass in.

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And that's why when we pass in the string object, we actually have the string, one plus string to

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just like what we had done year.

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Now this actually happens to be what we call operator overloading thanks to auto overloading.

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We are able to, for example, put in this class here and then automatically heighten calls this method

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for you and is able to join this too.

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And then if we are working with a list, you see it's going to be similar is going to join the two lists.

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If we're working with just this numbers, you see that as it up we can modify this say for example as

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if the two are equal, see is false.

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They are not the same.

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Let's modify this.

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We use that equal greater C.

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It's not the same because social equal your.

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So there we go.

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So if those objects equals or object, we have that.

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Now let's take this off.

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We see how we could use simpler patterns like this.

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And then this approach could be converted into your corresponding.

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Methods in the Python classes now coming back to smiley class.

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Let's define our equal method so we could define the equal method.

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Yeah.

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See, we have the object itself.

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And then we have another object which will call it the as M Smiley.

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That's the same object.

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Accent, object.

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There we go.

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We can solve that is smile equals as some object that is smile.

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So.

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Right.

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Yeah, we actually have two objects.

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We have this current object that a self which is presented by the self we have this object which I give

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is smile is the same as the other object is smile.

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If they are the same, then we're supposed not to smile.

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These are the same.

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So for now, let's run this.

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It's an area of no doubt when defining this operators.

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We need to have the double on this cause before and also after.

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And this method names aren't just some names we just guessing the actually in the python documentation

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for equals for equals is this for addition as we've seen is this.

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For subtraction is SOP.

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Anyway, let's do this.

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Yeah.

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So let's copy that.

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And then for multiplication.

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Small for division.

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We have to leave that to these and many artists so you could check on the documentation to see the exact

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method names we're going to use.

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So coming back to this, we have this equal does echo.

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Then we've decided to say that two smileys are the same.

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If the is smile attributes at the same one, this is fine.

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We'll define happy.

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I would define that.

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So here again, let's now call in the equal method.

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So here we have side the equal which takes in happy run.

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That is false.

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They are not the same.

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Let's modify this.

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We see they are actually the same.

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Not equal is actually not equal.

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So let's not do that.

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Let's have that same.

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It's okay.

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And then it's not equal.

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Take this off on that.

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And now that's modified this.

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Yeah, we have not equal.

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Okay, but not equal is supposed to be different.

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So let's put that wrong again.

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And there we go.

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We have not equal which is true states of not equal is true.

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So it means that sad and happy and not equal.

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Now what's interesting about overloading is that instead of doing this, we could simply see sad.

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I'll do that.

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I would say have the same response.

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So let's say instead of having this.

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Instead of having this.

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Sprint is out.

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So we say that instead of having instead of having to put it all like this, all we need to do is just

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now do this.

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So let's run that.

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Now let's come back to this year.

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And then commanders can see what we're getting now.

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So we have the same answer.

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Let's modify this and say equal.

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You see now is false.

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So this means we have the power to modify what our smiley thinks is o different smiley from itself.

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So the fact that we could modify this means if we want to say, for example, that for is for the equality

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of one, say for example, that for the two smiles to be equal or for the to smile is not be equal.

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We could specify that this is equal.

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So this could be equal.

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And and.

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We have.

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So that's at this.

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So to say that they are not equal, this could be equal and the the face colors could be different.

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So let's just copy this.

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Copy that.

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Now we just have this color face color.

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Face colour.

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So the face colour is different.

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It's going to be different from this now.

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You see that in this case is false and that is because the face color is different.

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It's common.

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This we still have the false.

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Now let's take this.

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Dear friend, you have to take this.

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We have truth to the modified is we have.

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Or then we suppose that if they have this as if the face colors are the same said that's true.

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See, this is not true.

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So the point we're trying to make here is we could simply use this kind of operators and then based

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on the class definitions, Python can automatically come up with some results.

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Let's consider again the object happy of the cross smiley to call on the set or out of the hat area

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method.

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Yeah we could have happy that hat area and then it gives us a hat area for that.

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Smiley Obviously we're getting the default values.

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We could say radius radius equals C two.

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There we go.

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We have a different value now.

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We could actually call this class as if it were a function.

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And to do that, we make use of the call operator overload.

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So we have the call.

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You have that now?

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Yeah.

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We shall return simply the head area.

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So we call in the head area method.

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That's fine.

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Let's run this.

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We'll see how this works now.

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So yeah, we print printers out, printers out, print this, print this.

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Now we have happy now this actually is our object which I just simply call that out goes on here is

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want to call this once we call this object here as a function it's going to use or be as if we're making

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a call on this method right here.

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So let's run.

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And there we go.

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We have the same answer.

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If we take this off this, we tend to that.

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I'll see.

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That's it.

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So that's the call operator of a loader.