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Now the next step is to think about reproducing the bug that you've encountered,

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because when you encounter it once but you don't encounter it the next time

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that becomes a really difficult bug to fix. Go ahead

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and uncomment the next block of code.

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And we're going to comment out the previous section because we're done with it

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now. So this is the only part that should be active in your main.py.

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In this section, we're going to try and reproduce the bug.

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So when we run the code,

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sometimes it will work and it will print out one of the dice images from this

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list, but occasionally you will get an error.

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These types of bugs are really difficult because you might test your code only

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once or twice, and it looks all fine. It works.

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But then occasionally you get an error.

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And the important thing is to reproduce that error.

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When does that error actually happen?

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And based on that knowledge, we can fix our code.

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Try to reproduce the bug yourself and try to notice when it happens and see if

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you can change the code so that it always produces this error.

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[inaudible],

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We've got a list of dice images, which are just emojis.

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And we've also got this random number, dice number between 1 and 6.

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Now, when we try to pick out of our list,

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occasionally we get an error.

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Now we have to notice when the error occurs, and to reproduce the bug

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we have to figure out which of these numbers is actually causing the problem.

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So we know that this is a random number between 1 and 6

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and if we check the documentation, it tells us that randint

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works a little bit differently from range.

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It will return a random integer in the range of a and b,

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including both end points. So in our case,

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both 1 and 6 could be generated and it could be any number.

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So if that was equal to 1, well, does it generate an error?

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No, it just picks out this particular item.

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But what if it was 2 or 3 or 4?

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Or what if we tested 6? Well,

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now every time we hit run, you can see we get an error.

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And now that we've got our error to show up consistently,

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it's a lot easier to debug because we know that the index error list index out of

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range happens when this dice number is 6.

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So when we go back to our previous code, well,

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we can't use 6 in this list because lists start counting from 0.

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So to get this dice 1, we need dice_num to be 0.

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And then this is 1, 2, 3, 4, 5,

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and 6 is somewhere out here and it doesn't exist. Now,

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go ahead and fix this code so that all the dice images are represented and we

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never see this error again. Alright.

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So that is as simple as shifting down these numbers.

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So instead of making a random number between 1 and 6,

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we actually want a random number between 0 and 5. And now,

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no matter how many times we run our code,

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we're never going to get that error show up again.