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In previous lectures, you learned how to access a single element in a list, and in this section you

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will learning how to walk through all the elements in a list.

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So you can also work with a specific group of items in a list called a slice in Python.

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So to make a slice, you specify the index of the first and last elements you want to work with.

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As with the range function, Python stops one item before the second index.

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You specify the output of the first three elements in a list you will request here indicates root zero.

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To.

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Three here.

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So now if you write 033023 here, we will get this here and this is our slice.

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So here I will create some examples here.

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So let's again make some example about car makers or let's sometime now, Yeah, car makers is okay.

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Car makers here we will add BMW, Honda here.

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We will add Volkswagen.

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We will add the fourth.

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And I.

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Here.

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And this sun here.

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So here we will print print the zero three.

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So print carmakers.

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Carmakers zero three here.

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So this code now, let this code prints a slice of the list so the output retains the structure of a

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list and includes the first three carmakers in the list here.

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So in this case, it's going to print us here.

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It's going to print us BMW, Honda, BMW, Honda and Volkswagen.

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So it will print us these three items as we write in zero and three here.

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So now let's print this.

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And as you can see here, BMW, Honda, Volkswagen.

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So you can generate any subset of a list.

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For example, if you want to if you want to if you want to second and second, third and fourth item

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in a list, you will do this.

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Here.

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As you can see here, we started Honda, Volkswagen and Ford.

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And this time the slides start.

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Start with Honda here and ends with the Ford.

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So if you omit the first index and a slice Python automatically starts your slice at the beginning of

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the list.

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Like this here.

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You just need to add this double dot here.

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And as you can see here, we got BMW, Honda, Volkswagen and Ford.

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So.

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So a similar syntax works if you want to slice that includes the end of a list.

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So for example, if you want to, um, all items from the third item through the last item, you can

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do this two double dot, but this double dot here will have, will, will come after the number to get

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the last item.

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So here we get from the last item.

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Now in this case, we will get, as you can see here, let's actually.

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Where is my marker?

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Yes.

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So here we got Nissan.

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Kia.

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Hyundai.

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Volkswagen.

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And that's it.

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We got from here to here.

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So we got to here.

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We counted zero one second.

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And from second we told Python that get all those items from the list.

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So.

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Now Python returns all the items from the third item that through the end of the list.

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So I can afford and Nissan.

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So this syntax allows you to output all the elements from any point in your list to the end, regardless

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of the length of the list or something.

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So recall that a negative index returns an element a certain distance from the end of a list.

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Therefore, you can output any size of the end of a list.

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For example, if you want to output the last three carmakers on the carmakers, we can use this slice

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like this here.

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Minus three, negative three here and this double dot here and after that.

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We will print this.

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And as you can see here, we printed Hyundai, Kia, Nissan here.

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So you can actually include the third value in the braces indicating a slice.

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So if a third value is included, the test Python, how many items to skip between items in the specified

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range.

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So you can use a slice in a for loop if you want to loop through the subset of the elements in a list.

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So in this example, we will loop through the first three car makers and print their names as a part

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of a simple car maker.

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Now we will print here, here, here are the first.

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First for.

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For car makers in my list here.

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And after that we will use for loop for car maker.

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Car maker in car makers.

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And here we will enter this.

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Here for.

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And after that, we will play print here.

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Well print the carmaker dot title.

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So here we will.

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Let's run this.

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And as you can see here, we got this example, We got this output.

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So instead of looping through the entire list of players or car makers, Python loops through only the

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first three first for car makers.

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So slices are very useful in a number of situations.

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For instance, when you are creating a game, you could add a player, you could add a car makers model

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to a list.

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Every time that that car is running or playing, the player is playing with that car.

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So you could then get a player's.

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Top three scores by sorting the list in decreasing order and taking a slice that includes just the first

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three scores.