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Hello guys.

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Welcome back to another class of our course about Python.

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So until now we talked about a lot of interesting things which are variables we talked about data that

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you can store in your variables.

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We created apps to put everything together.

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And until now you have small but pretty good knowledge of python.

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So in this class we are still going to continue talking about data up data manipulation.

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So my goal right now is to show you another way that you guys can store your data so you can store your

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data into a variable so we can store in number a string or a boolean instead of a variable.

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But let's say you want to store a bunch of data at the same place.

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So this is where lists come into play.

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The list is simply a variable where we can store more than let's say one data.

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So let's say for example let's take a variable so I'll write down here variable one and the variable

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one.

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Let's say I want to store a string instead of it.

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So let's say I store Apple so you can see my variable number one has only one element in it.

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So it has only one string.

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But let's say I want to create a list.

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So in this case I'll write.

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Don't list one.

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It starts the exact same way but right now to write down my list what I'm what I need to do is open

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up those special parentheses and I can start writing down the all the all the other ones that will be

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my list.

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So let's say I have apples I have bananas I have.

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And then this

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and I have melon.

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So fruits.

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All right.

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So as you can see if for example I decide to print the whole list.

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So in this case it will be list 1.

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So what will happen is that python will print the whole list as you can see I have my four of my four

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elements right here which is apple banana and on us and melon.

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But let's say right now I want to work with my list and I want to print only one of those elements so

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in this case let's say I want to print only Apple.

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So the way I explained you guys Python works Python well in this case python will use indexes but how

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indexes work is very simple.

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The first element is always the element 0.

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So in this case Apple will be equal to zero.

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Banana will be equal to one and S will be equal to two and million will be equal to three.

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So let's say I want to print the first element which here will be the element 0.

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So how I will do this I will write down my friend function.

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Then I write down the name of the list for the variable that I want to print.

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And in the case that if it's a list I will still open up my parentheses.

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And in this case I will select the number zero.

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So let's say I want to print Apple so I will simply write down zero which is the index value of Apple.

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And as you can see I just print that out.

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Apple if only print out banana in this case I will simply write down number one and I printed test and

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see it writes down banana all right.

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So right now you know exactly how you can select the right value to print.

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So let's say for example Apple banana or us.

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You simply write don't print you write down your list.

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So in this case list number one and you select the index value that you want to print.

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So you want to print number one number zero one two three.

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Next thing let's say for example right now that you want to modify what's in here.

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So in this case for example we have Apple we have banana and we have a..

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But let's say I want to change melon by.

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I don't know avocado so in this case what I will do it is very simple.

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So I write down my list one and I will open up my parenthesis and then this case I will select the index

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of melons or melon will be the third index.

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I write down equal.

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And by and I write down by what exactly I want to change melons so in this case I want a change melon.

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But full cattle then when it's all done you can simply print this let's say in this case I print this

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so list

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and as you can see here it all changes.

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So I have apple I have banana.

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I have an illness and I have avocado instead of melon because I just changed my Yeah well my my element

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right here which is melon.

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I change it by avocado.

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I can't do it on multiple elements so let's say for example I want to change the element number two

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as well so you can just write down list.

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So list one and I changed the element number two which is unless I can change it by I don't know to

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me.

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So in this case I'll change you by to model and if I print list one once again you'll be able to see

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apple banana to me you and avocado.

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So as you can see guys it's very very simple to use.

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So this is a way that you guys can print.

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You can print elements so you can see it's very very simple too.

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Well very simple to work with lists in the basic ways.

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If you want to select an element and if you want to modify an element.

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All right.

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Another thing that you guys can do with lists in this case would be selecting only one of the elements

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or multiple elements but not all elements.

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So let's say for example right here I have more than four elements.

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Let's say I want to have.

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So I have apple bananas and a nice melon strawberry

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and other

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right.

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And right now I only want to have the element number let's say two.

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So banana.

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So how exactly I will do this exact same thing.

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So simply I will print.

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So I use my print function I write down list number one.

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So in this case list number one and I open up my special parentheses and I write down so what I said

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is I want my banana.

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I want my N.A. so banana is the number one and an S is number two in our Python index.

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So what I want to write is from 1 to 3.

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So what's going to happen here is that python will give me will return the number one and the number

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two but will not return me the number three.

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So let's say I print everything right here.

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So I have my banana and my N.A. if I want for example to print that my banana my antennas and my melon.

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In this case is going to be from 1 to 4.

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And if I print it.

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Well as you can see I will have banana and an S and melon.

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But let's say I want to print everything but not the apples.

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In this case I can just write it down like this.

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So it's gonna be print list one and two points and they leave it empty as you can see it's gonna print

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absolutely everything.

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If I start printing from an n as well in this case I can just write them too because it's gonna be index

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zero index 1 and index 2 and I start to print from index 2 and index 2 is included so I'll have an A.M.

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melon strawberry and other so you can see this is a basic manipulation of lists and what exactly you

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can do with it.

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And as you can see it's not that hard to do and it's not that hard to use.

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Well as I explained if we summarise absolutely everything difference between the list and a variable

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is that a variable will have only one element in it.

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It could be a string could be a boolean it could be a number but in the case of a list it's a it's absolutely

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different.

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You can have all the trees so we can have numbers boolean and strings and what is school is that you

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can work with all those at the same time.

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So at the same time you can select one of those and you can work just with this only element.

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So right now you know the basics of lists in the future we are going to talk about more advanced functions

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about all those lists as well.

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So that's it for the sports guys and see out in our next class.