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Welcome back. Now, let's spend a bit more time to talk about strings.

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So far, we've worked with the hello world string.

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And I did say that whenever you're wrapping your text,

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you typically want to use double quotation marks. However,

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that's not always true.

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The default is to wrap your text with double quotation marks. However,

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you can actually get away by using single quotation marks.

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So let me just go over here right now and

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edit that.

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I'm using single quotation marks. I press run

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and you can see it works perfectly fine.

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So you don't always have to use double quotation marks.

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The natural question you might have here is OK. So when do we use single?

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When do we use double? Does it really matter?

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In most cases, it really comes down to your personal preference,

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whether you are a single quotation user or a double quotation user,

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the default most programmers tend to go with the double

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quotations

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and there are instances where you could actually even use both of them

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in the same string

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as an example.

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What if I wanted to say

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something like he said

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hello?

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Right.

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So let me just go over here right now

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and say,

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he

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said

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and

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going to say hello,

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how would we be able to print this out successfully?

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Because if we click run right now,

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it's gonna give us an error message.

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Ok, we need to wrap these texts, these letters in quotation marks.

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But how do we go about it?

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Well, we could do this.

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I could go over here right now.

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Add a single

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quotation mark. Oops, sorry,

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it has to be inside.

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So the single quotation mark first.

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OK.

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And now for the actual words that he said hello,

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I'm going to use the double quotation marks in

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here to wrap the exact word hello itself.

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And then

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whenever actually this is pretty common in programming languages. OK?

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Whenever you have like an opening quotation mark,

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you want to have a closing quotation mark as well. So I'm gonna add

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the single quotation mark right there.

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And now if I click run,

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you can see right now it actually works.

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We could do the exact opposite.

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I could start off with a double quotation mark. OK?

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And then I'm gonna come over here right now, wrap hello

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in the single quotation marks and then

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add the closing

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double quotation marks run and you can see it works perfectly fine.

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However,

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what if I wanted very long strings, right? So I do have my Epsom

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generator in here. So let me just grab

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this first paragraph over here. OK.

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Copy, come over here.

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Now,

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I could actually

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wrap everything as big as it is

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inside of the double quotation, mac click run

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and it's gonna work perfectly fine.

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But what if

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I actually wanted to create some space? And so, for example,

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I wanted to have some space in here.

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I come over here right now and add some space in

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right now. It's all kind of disorganized.

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I click run.

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And now we're gonna have an arrow message.

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It's not working anymore because Python cannot understand

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the space in between the lines of text.

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So

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this is where

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the triple quotation marks will come in. So watch this. OK.

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I'm gonna add 123.

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Okay. Oops, sorry about that.

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That is three. OK?

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And of course, I'm gonna come over here right now

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and add

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the close in three quotation marks. And now if I click run

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and there you go,

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you can see it actually works. So

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there are certain instances where you may want to use triple quotation marks if

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you have very specific kind of spacing.

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Uh It's also typically used for like uh documentation, lighting lines of code,

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things like that.

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That's where you would use the triple quotation marks.

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Now, we could also combine strings,

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all right.

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So as an example, let me quickly show you, let me create a new variable here and say X

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OK

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equals and then in double quotation marks, I'm going to say hello.

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OK?

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And then I could create a second variable Y

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equals

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world.

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OK?

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And now

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if I wanted to combine both of them,

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I could say print

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parenthesis very simply

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X plus

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Y.

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And now if I click run,

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there you go. Hello world.

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But if we wanted to add the space between hello and world, all I can do

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is I can either add the space at hello right here.

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So I've added the space after the o click on run, You have hello world or

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I could do the opposite

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and simply add the space at the beginning of W click on run

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and there you go, you have the exact same result. Now let's

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make this just a little bit more sophisticated, this program,

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just a little bit more sophisticated.

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I'm going to introduce to you a new function

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called input. So so far we've been working with print.

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Now let me introduce to you input. So input is basically a function that will ask

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the user to provide something. OK? So

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I'm going to say input and then in parenthesis, I'm going to say say something,

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please.

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OK.

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So if I run,

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oh, sorry about that. If I run the command,

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you can see right now you say say something, please. And now if I say

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hi, my name is Alex and I press enter,

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nothing happens.

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OK? Because

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our program, all it does is to ask the user to say something

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and that's it. It's not going to do anything with what the user has actually said

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so to make this a little bit more advanced, I'm gonna go back

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in here.

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Let's remove this

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and let's create a new variable. I will say user

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response.

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OK? This is going to be the name of my variable. And by the way,

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let me just say something real quick.

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It's good etiquette,

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good programming etiquette whenever you're creating names for your variables

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or your functions and you're combining two words together.

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In this case right now, I'm combining user and response.

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The

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second word, the first letter typically should be in capital letters.

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That's why the R for response here is in capital. I'm just saying, OK, so just

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bear that in mind. So

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here the response equals

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OK?

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And I'm gonna say input

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and now

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in brackets, I'm gonna say,

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say something,

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please.

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OK?

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However,

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I'm going to come down here,

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I'm going to now

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use

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the print

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function

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in brackets,

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gonna say user response.

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That's it

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pretty straightforward.

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I'm gonna go ahead right now. Run the command.

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It says say something, please. So I'm gonna say

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my name is Alex Press enter and there you go.

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Now, it's saying my name is Alex.

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So successfully introduce to you a new function which is input,

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which will ask the user to provide something.

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We've talked about how

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to use the single quotation marks,

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the double quotation marks as well as the triple quotation marks.

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And I've also shown you how we can actually combine strings

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by creating multiple variables and simply using the plus operator

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to combine them.

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So gradually,

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gradually we're getting better and better at walking with Python and string.

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So

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thank you for watching the video. And of course, I will see you in the next class.