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Often your lists will be created in an unpredictable order because you can't always control the order

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in which your users provide their data.

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Although this is unavoidable in most circumstances, you will frequently want to present the information

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in a particular order.

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Sometimes you will want to preserve the original order of your list and other times you will want to

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change the original order here.

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So Python provides a number of different ways to organize your lists depending on the situation.

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We can also sort the list permanently with a sort method.

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So let's first create a list here that we can conduct our experiments on.

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In this case, it's going to be cards again.

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So it's going to be Toyota or yeah, Toyota.

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Audi or.

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Yes.

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Yes.

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BMW.

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Audi.

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Audi.

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Here.

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Toyota.

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Bar.

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That's a.

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And here.

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So I want to talk about the sort method.

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So the sort method makes it relatively easy to sort a list.

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Imagine we have a list of cars and we want to change the order of the list to store them alphabetically.

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To keep this task simple, let's assume that all the values in the list are lowercase.

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Now, actually, instead of assuming this, actually use this lowercase method and we can use the title

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or uppercase methods.

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So make so good.

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So here we will use the cars that sort.

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And we will after that.

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Print.

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Cause That's it.

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And as you can see here, A, b, s t here.

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So the sort method changes the order of the list permanently.

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The cars are now in alphabetical order and we can never revert to the original order here.

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So you can also sort the list in reverse alphabetical order by passing the argument reverse true to

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the sort method.

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So here we in order to do that, we will use reverse true.

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And here.

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So the first example was, uh, here, let me fix my mouse right now.

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Yes.

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So the first example was the, our first example was.

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This is the row here that we entered, which is the first was BMW.

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We.

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M-W then Audi.

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And then Toyota.

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And then Subaru.

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This is the first row here.

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And then with sort.

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Let's actually use a different pen.

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And here with salt here.

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I'm sorry.

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And after that, here we have Audi, BMW, Subaru and Toyota.

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So we will delete this.

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And now we will create a new sort here.

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Car, that sort.

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Reverse.

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True.

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And print cars again.

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That's it.

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And this is how it works.

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Firstly, we sorted the cars out.

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The BMW is here and as you can see in alphabetical order, it's the Scandic, right?

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A, B, C, so TSB, A and a, B, C.

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We can also sort the list temporarily with the sorted function so the maintain the original order of

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the list but present it in a sorted order.

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You can use the sorted function.

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The sorted function lets you display your list in a particular order but doesn't affect the actual order

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of the list.

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So let's try this function on the list of our cars.

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So here.

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We will use assorted cars, cars of assorted cars.

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And here, let's print this.

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Cars.

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And as you can see, it's the same.

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But now look at this.

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In order to save this sort.

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So in order to make it permanently, you will do cars equals sorted cars and this is how you make it

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permanent.

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So here we will write.

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Print.

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Print.

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Sorted.

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Sorted cars.

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I'm.

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And here we will print the cars again.

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And as I said, this is temporarily.

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That's why it changed backwards here, the original here.

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So we first here, we point the original order and then in alphabetical order.

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And after the list is displayed at the new order, we show that the list is still stored in its original

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order.

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We can also print a list in reverse order.

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So to reverse the original order of layers, you can use the reverse method.

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So if we originally stored the list of cars in chronological order according to when we owned them,

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we could easily rearrange the list into reverse chronological order.

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In order to do that, we will use first print actually cars.

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So we will see and hear after that.

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Cars dot reverse.

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And after that print cars.

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That's it.

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We've also entered the Subaru.

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So here we have Subaru, Toyota of.

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Toyota, Audi and BMW.

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That's it.

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And notice that the reverse doesn't sort backward alpha tab alphabetically.

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It simply reverses the order of the list and the reverse method change the order of a list permanently,

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but you can revert to original order anytime by applying reverse to the same list a second time.

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Let's try this now.

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Cars dot reverse and print.

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That's it.

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And here, as you can see here, this is the original original, but it's two times reverse here.

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We can also find the length of list here so you can quickly find the length of list by using the Len

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function.

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The list in the list in this example has four items, so its length is four.

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So now we will.

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BMW here.

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Oh, the.

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We are created.

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Sorry.

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And then here.

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Print, Len.

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Cars.

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And thus you can see here it showed us for.