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Hey, in this video, you will learn how to have your program take decisions.

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In other words, you can make your program more intelligent so that it responds to different ways depending

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on the user inputs.

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So exactly what we'll be doing is we will allow the user to decide what they want to do.

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So whether they want to add a new to do or to see the existing list of two zoos, because currently

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the way the program works is that the user can enter it to do and they see the list of to dos, they

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enter another to do.

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They see the list again.

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So how about not showing the list by default, but only showing that if the user wants to see it, we

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can implement that using the match case statement.

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Now, Match Case is only available in Python 3.10 or newer versions of Python.

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Therefore, for this to work you need to use at least Python 3.10.

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Right.

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So how do we implement this decision making?

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Well, first, we want to ask the user if they want to add a new to do or if they want to see the to

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dos.

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So what I'm thinking is of changing the message here to type, add or show.

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So that's just a string.

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The string goes in here.

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I would simplify this actually, and just put the string directly here so we don't have so many layers.

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Both versions are fine.

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But I do think this is a bit more readable.

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So by looking at this, you understand that you are asking the user for input.

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Since this is an input function and you see what message you are showing to the user.

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Now the user is expected to enter, add or show and add or show will be stored in this variable.

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So to do will be equal to either add or show.

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But I want to change the name of this variable now to make it more meaningful.

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User action would make more sense.

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And then we say.

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Match user action.

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A column and press enter and you'll see that points are automatically indents the next line.

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So this match is a block match.

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Case statement is a block just like while through so much user action case and.

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To do is equal to input.

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Enter a to do.

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Let me complete this and explain it to you.

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What I'm doing is show.

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Print to dos.

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And this will go down here.

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And this will be deleted.

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And that's the complete code for this video.

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Now, let me explain to you what this means.

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So we start here, match user action.

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This variable, as I said, is this one here.

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It will be either add or show.

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So we're trying to check here the value of that variable.

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We're trying to match that variable.

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So if the value of that variable is ad, so if the case is ad, then what we do is we ask the user for

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A to do so, they will be prompted again to enter some inputs.

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They will enter it to do such as clean the bag.

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That to do will be appended to the list.

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To that list.

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And that's it.

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If the user action was show, So if the case is true, then we print out to dos.

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So let me execute this.

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And so we get this user prompt type ad or show.

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If I press, show and press enter, we're going to get an empty list because currently there are no

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to dos.

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So if I press add, then I get this.

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Prompt to enter a new to do.

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Clean the bag, press enter again we get type, add or show.

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Why do we get again?

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Type and or show?

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Well, because when we were asked to enter a to do, we were at this point.

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And we entered it to do this was executed.

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And so.

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The loop will be repeated again, so it will go and ask for type at or show again.

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So a user enters, add for example, add a stored in the user action variable.

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The match case again checks.

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If it's ads, it does those things.

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If it's show, it does that thing, and then goes back again to the first line of the wild through loop,

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which is this line here.

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And so the loop iterates over and over again.

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Now, how about adding one more option here?

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Type at show or exit?

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So the user can also enter exits.

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In that case, we want to add another case or case exit.

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We want to exit the program.

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At this point, the way we do that is using the break statement statement.

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So it just writes break there and that will break the while loop.

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And so since there are no more lines of code down here.

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The program will end or you can add here print by and let's see how this works.

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So we run the script.

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Type ads show or exit ad.

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Prepared the highly copter type and show or exit exits.

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We get by and the process, the program finishes its execution and that is the complete code for this

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video.

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Thank you.

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I'll see you later.