Original subtitles

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To begin,

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I want you to locate the day 1.2 debugging exercise.

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And now, as you did before, go ahead and read through the instructions.

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Be mindful that the output must match the example output precisely.

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And when you hit run, this is the outcome you're looking for.

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So there's quite a few things broken here,

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but I want you to have a go at fixing each line individually and pulling out the

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bugs from the code. So pause the video now and give that a go.

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All right.

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So how did that go? If you haven't got your computer in front of you,

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if you're traveling, if somehow you can't access the exercise, just pause

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and when you've got time,

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then complete the challenge and then come back to the course.

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It is so important that you actually do some hands-on stuff.

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And I stress that this is the only way that you are going to become the rock

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star coder that I know you can be. Let's take a look at the code below.

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You can see that when we run our code as it is right now,

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we get a new error.

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And this is going to point to the first of many errors in this file.

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And in this case, it tells us that on line three,

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so this one right here, at around this position

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or somewhere around here, um, as denoted by the little caret sign,

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there is a syntax error. If we study this closely,

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you can see that the code highlighting seems to be suggesting that all of this

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is code, but this is somehow text. So what's going on here?

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Well, notice that we've only got one double quote.

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So it thinks that what comes after this is the text,

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but what comes before it, it thought it was just a continuation of code.

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So to fix this one,

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all we have to do is add a double quote right here. That changes the text to the

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color that we're used to and this fixes this line.

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So if we run our code now, we should get a different error. And indeed we do.

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The next one tells us that on line five,

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so this one right here, there is an indentation error.

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There's an unexpected indent somewhere around here on line five.

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So let's take a look at line five and there you go.

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There's a little bit of extra space between the print and the beginning of the

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line.

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So now that we've fixed that one, let's click run. And it will point to

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another line of code that's broken. And in this case,

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it says on line seven,

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which is here where there's actually no code,

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there's the unexpected EOF while parsing. What does this mean?

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Well, if you're not sure,

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then go ahead and paste it into Google and let's take a look at what people say

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on Stack Overflow. So as this person,

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very kind, Felix, um, has explained, this index error

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unexpected EOF

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while parsing means that the end of your source code was reached before all

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code blocks were completed. What is a code block? Well,

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this is a code block because it's a print function,

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it has a beginning and it has an end. But what does this line not have?

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Well, it's got two open parentheses,

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but only one closing parentheses.

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So the computer thinks that you are going to continue writing something and then

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close it off at the end, which is not the case. In fact,

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what has happened is we simply have an extra misplaced open parenthesis.

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And now if we delete that and hit run,

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you'll see that we have everything printed.

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But at this point, notice how on line four

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which is the line that we haven't fixed yet,

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it prints string concatenation is done with the 'blank' sign.

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Whereas in fact, it should say plus sign.

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And even though we don't see any errors being printed in our console,

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you'll see that we have an output mismatch because I'm expecting to see this

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line, the String Concatenation is done with the "+" sign,

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but here,

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the output doesn't have that part. It's missing this part.

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So there's one last thing that you need to debug. And that is of course,

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on line four.

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And what's happening here is we have this part being interpreted as a string,

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this part being interpreted a string,

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and it thinks that this plus sign is just us concatenating

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these two parts together,

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which is why it printed out like this. But in fact,

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we wanted to print out is this as text down here.

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So what we have to do is to change this outer apart from double quotes

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into single quotes.

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And now you can see when it highlights this part,

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it's all the same color including the plus sign.

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Now it sees this as a complete string,

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and it's not looking at this as if it's code. So now if we run our program,

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you can see the entire sentence being printed out.

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So if you've completed the challenge and you've gotten everything right,

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then you're now done with this exercise.

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If you got stuck and you want to have a look at the solution, as always it's down

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here,

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and it might be useful to have a look at this page to see where you might've

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missed something or where you might've gotten something wrong.

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So I hope you enjoyed this code exercise. In the next lesson,

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we're going to learn about a new type of Python function,

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which is the input function. So for all of that and more, I'll see you there.