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Hey friends, welcome back to our Python
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journey and today we are going to go
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through module four. We are going to
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talk about one of my favorite topics
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which is lists and Python.
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Why are lists so cool?
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Well, because they can hold anything.
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Could be numbers, strings, even other
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If Python is that flexible.
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So what exactly is a list?
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So think of it like a shopping bag. You
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can throw in apples, bananas, milk, and
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maybe even a smaller bag with cookies
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So that is actually something like a
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Python list. It could be ordered. We can
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change it and it can hold different
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types of items. Maybe list inside the
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list or as well. like if you see here
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So let's start with the syntax of the
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list. So to make a list you just have to
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use the square brackets and separate the
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items with commas. Let me show you like
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for example numbers. I just create I'm
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creating a list. So now at this point
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Python is thinking it as a variable but
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later when you give list.
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Okay. Now you see Python is taking the
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And now when you print numbers
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it will print the list.
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So to make a list you just have to use
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the square brackets and keep the items
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inside the list separated with commas.
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And you can create even fruits
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list here. Just create it. So always
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fruits are you know you'll give string.
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And you can create mixed list like uh
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where you can keep everything like you
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any boolean data which is either true or
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false. And you can also keep list inside
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So you can add multiple items at once.
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And when you print this, print mixed
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So it will just print everything you
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doesn't mind. It can, you know, add the
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numbers, the string, the boolean data,
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true or false, and a list as well.
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Sorry, my throat is really bad today. A
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So now, how do you grab something from
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your list? Like in order to print, I
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just want 10 from this one. How do you
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do that? Well, for that we use a concept
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called index. In Python, the counting
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starts from zero. Not just in Python, in
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any programming language. when you're
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giving anything in the list or it could
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be an array in other programming
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languages. So you always start with zero
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2 so 0 1 2 3 0 1 2 3 4 something like
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So in order to get the first item you
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have to just give mix the list of zero.
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So when you do that it will just print
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See and when you give one
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then it will give you the second item
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So this is the second item. So zero
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think of it like a memory. It is saving
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it as a zero memory and the first one
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and the second one and the third one.
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So the position of 10 is from my list of
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zero. The position of Python is one and
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So what if we want the last item? You
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So then it will just give you the last
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item. But now I know that there are four
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items in this list. Sometimes I don't
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know how many items are there in the
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list to get the last one last position.
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So what I can do is I can just give
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minus one to get the last position when
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I don't know the length of the list like
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the size of the list the number of items
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in the list. Then if I if you just give
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minus one then it is going to get the
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last one for you. If you give minus2
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then it will give you the last second
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one. It's like you're telling the Python
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hey Python get me the last item from the
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list last second item from the list.
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So the positive numbers count from the
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front like 0 1 2 3 and the negative like
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if you want from the last one then it
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will be min -1 -2 you know minus 3
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something like that don't worry if you
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just if you practice more then you're
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going to you know get more idea on how
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So why lists are amazing? I could say
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because they keep order like the items
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stay in the order the way you put them
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and they are mutable. It means you can
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change or add or even remove the stuff
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from the list and they are flexible. If
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you see they can hold anything. If you
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see in other programming languages like
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for example if you see arrays so there
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you just have to give numbers you just
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have to give strings you just have to
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give boolean something like that but
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here you can give whatever the data that
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you want and it will you know take the
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values flexibly according to the needs.
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So here we have actually saw that lists
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are actually a collection of items that
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you keep in a you know brackets in a
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square brackets separated with comma
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something like this. Okay, we can change
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them, we can add, we can remove the
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list. And why they are amazing? Because
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they follow the order. The order that
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you give element one, element two,
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element three. And it will start from
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zero. The position of the first element
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in the list starts from zero. And it can
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hold any data type, number, strings,
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anything. So this is how you will create
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numbers in the list. You can create
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fruits in the list. You can create
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everything. You can keep a number, a
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fruit, a boolean and even a list.
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So it can access and we can access
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elements by index which is nothing but
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we are just going to give the position
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like imagine that there is a box holding
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in zero and one banana is holding in one
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and orange is holding in two and
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strawberry is holding in three something
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And when you want the last item then you
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will just do minus1 in the brackets.
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Then it will give you the strawberry as
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And in the next video we are going to
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work on the list built-in functions. So
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it flows directly after this one. Yeah.
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Don't forget to like, share, and
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subscribe. In the next video we are
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going to work with list built-in
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functions. See you in the next one.
