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The goal of this exercise is to practice

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what you have learned about the print() statement in Python.

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So using what you know,

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including the syntax of the print() statement,

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which symbols you need to type

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in order to print out each of these lines,

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try and figure out if you can modify the code, add to it,

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and when you hit RUN,

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each of these five lines should be printed out separately

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into the Output area at the bottom.

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So try and figure out if you can do this

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and take a look at the Instructions pane

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to help you and guide you through this exercise.

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Once you're confident that your code is doing exactly

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what it's meant to do,

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hit SUBMIT and test your code against the test cases

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that we have prepared for you.

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Now it's really important that you print out

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exactly word for word, letter for letter,

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what we have in the example outputs,

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no extra spaces, no extra full stops,

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just be really, really careful

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because the match has to go through exactly.

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It has to be precisely the same.

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So just be careful with that, and have a go.

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All right, so on this slide,

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I want to go through the code solution with you.

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And this is a read-only code base,

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so you can't change it, you can't touch it,

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but it does show you exactly what you need to type

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or to change to the previous exercise

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in order for it to pass all of the tests.

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Now in this case, we want to print out

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five of these statements each on their own line.

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So we need five different print() statements.

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And the print() statements syntax is very simple.

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We use the keyword "print"

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to tell the computer our intention,

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we want to print something into the Output area.

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And then we define what we want to print

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inside a set of parentheses,

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which is also known as these round brackets ().

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Now, inside the round brackets,

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we can define what it is we want to print,

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and in this case, we want to print text.

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So we've put the text in between a set of double quotes

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to tell the computer this,

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even though it's written in a similar way,

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like you might see code, this is not code

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and it doesn't have any actions for you to do,

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instead, it's just text that I want to print

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into the Output area.

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So now when the computer reads this file from top to bottom,

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from left to right, it knows exactly what it needs to do,

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and in fact, if you hit RUN CODE,

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you'll see all five of these statements print out

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one by one, each on their own line.

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Now, if you had any issues passing the previous test,

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make sure that you don't have any extra spaces,

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extra symbols, anything is going to change the result there.

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And if in doubt, at the end, you can also just copy

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this entire five lines of code,

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paste it into the previous slide

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and see if it passes all the tests,

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and maybe you'll figure out what the issue is that you had.

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Now, in addition to the basic print() statements

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that you saw before,

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you can also add some modifiers to our text

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in order to achieve a specific need.

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So for example, in this case, in the first print() statement,

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we want to have some double quotes

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around an actual quotation,

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so the word "Hello".

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But notice the color coding here.

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Because the computer reads from left to right,

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when it sees the first double quote,

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it thinks, "Uh, this is the beginning of text,"

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and then it sees the second double quote

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at the beginning of the word "Hello"

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and it thinks, erroneously, that that is the end of the text.

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So then what comes after the end of text?

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Well, it's code.

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Look at how the word "Hello"

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is highlighted in the same color as the keyword print,

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this computer thinks that the word "Hello" is a command,

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it's an action, but it's not.

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Instead, it's actually us trying to use

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the English language grammatical syntax

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to put the double quotes around something

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that has been spoken by someone.

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So how do you solve this?

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Well, a really simple way is to alternate the use

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of single and double quotes.

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In Python, we can define a piece of text,

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which is also known as a string,

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using either a single quote or a double quote.

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Depending on what it is that you need

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to have inside the string,

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for example, in this case, we want to use double quotes

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inside the text area,

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then we can instead use single quotes to define our text.

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So this way, because the single quote

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and double quote are different,

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the computer knows that this is the beginning of text

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from the word "She said",

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and then at the end,

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"then left." is the end of the entire string.

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And in the middle,

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we can have our English grammatical double quote.

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So just by alternating this,

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we can have either double quotes inside our text

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or single quotes inside our text

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by using a different type of symbol.

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Now, another alternative option

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that I want you to be aware of

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is the use of what's called an escape backslash.

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So this when you see here, it says, She said,

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and then we've got a colon,

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and then we have a backslash right before the double quote.

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So even though in this case we've got double quotes

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inside double quotes,

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which as we said in the beginning can be confusing

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for the computer to know what is text and what is code,

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but because we have the backslash (\)

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in front of the double quotes that we want to keep,

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then the computer knows to ignore this as code.

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So yes, the double quote can be used

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in English to denote speech,

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but also in programming, it's there to be placed around

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words to tell the computer that it is text.

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But in this case, we add the backslash

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in front of the double quotes in the middle of the sentence

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to tell the computer, "Ignore this.

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This is definitely not code.

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Don't worry about it.

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It is meant to be printed exactly as it is."

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So these are two of the ways

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that you can modify your print() statement

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if you want to add symbols

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that are used within the syntax of the print() statement.

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So you've heard the theory

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of how to modify print() statements,

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but now let's see it in practice.

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So here, I've got the three examples that I talked about

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where you can alternate single and double quotes,

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and you can also use the backslash

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in order to escape a particular symbol.

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So go ahead and run this code and see what it prints out,

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and then see if you can mess around with the code

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to make all of this knowledge your own

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so that you understand exactly what's going on

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and what I mean by all of the explanations

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that I gave in the previous slide.

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Play around with the code,

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you won't be able to break anything,

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just try it out and make sure you understand

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what's going on.