WEBVTT

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In this new activity, you will take an input from the user, let's say 0 or 1, and if the user gives

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you zero, you turn off the LED.

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If the user gives you one, you turn on the LED.

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So here zero means turn off and then one means turn on.

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And you're going to use the input function okay that we have seen previously.

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So you will have first to set up the LED with the Gpio zero module like we did in the previous lesson.

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And then to get the number from the user you can use the input with a nice input message.

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So you can put a message here so the instruction is clear.

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Then you can put this input result inside a variable for example user choice like this.

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And of course don't forget to cast to an int.

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So the whole thing because what you're going to get is a string that you want to cast to an int, okay,

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to get 0 or 1.

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So after you get the input, what you can do as an additional step is to validate Date that input.

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Why we validate that input?

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Because we are expecting 0 or 1.

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But if the user gives you -1 or 10 or any other number, well, that's not valid.

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You want to have exactly 0 or 1.

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So if it's zero you turn off.

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If it's one, you turn on.

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If it's any other value, you're going to print an error message and you're going to exit the program.

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To exit the program, you also have this keyword exit.

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So if I write exit and the Python interpreter reaches that line, then it's just going to exit from

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the program, even if I have additional instructions after that.

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So if I have anything else, for example minus six then we're gonna print a log and exit.

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So not just minus six, it's just an example but any other number.

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And well, after you turn off or you turn on, maybe you wait for two seconds.

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Okay.

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So you can wait for two seconds before you finish the program.

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And that's basically it.

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Okay.

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So with this you will practice with the LED but also with conditions.

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All right.

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Now I will see you in the next lesson for the solution.