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So we just created a program that isn't going to air out, hopefully at least with Vallieres and Zero

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Division airs.

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But sometimes errors and exceptions can be so severe that we do want to stop our programs from running.

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We do want to catch them like this with the block, but at the same time also stop whatever the program

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is doing.

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Maybe instead of print, we actually want to display that red here and says, oh, something bad's happening.

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Stop that.

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Well, in that case, we either don't use the except block or in here we can say raise.

9
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Value air.

10
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Now, this is rare that you would have to do this.

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There are some specific use cases, but here you just write a message saying, hey.

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Cut it out so that if I run this.

13
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Well, if I type in a valid number, I get please enter a number, OK, I'm finally done because I raise

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a value error.

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And it throws in here into the book, so I'd have to remove this and if I remove this like this and

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hit Ron.

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And five and look at that, I get a value error, hey, cut it up so I'm able to throw my own eres.

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So this is really useful if you're creating your own library or tool and you want to let the user know

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that an error happened, I'm not going to keep doing what you're doing.

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And this could be any type of error, you can also do something like exception, and if I click run

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here, do five.

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I get an exception.

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Hey, cut it up.

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The key thing to remember with Ayres is that errors are unavoidable in programming, what your job is

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as a programmer is to be able to anticipate these errors, these bugs, these exceptions, and handle

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them properly in your programs.

27
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And some of the biggest errors happen when we're trying to accept input from a user not just using this

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input, but functions, accepting arguments, classes, accepting different inputs from users like method

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calls and trying to change attributes when the outside world in our programs try to communicate with

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each other.

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Errors are bound to happen.

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Our job as programmers is to try and code in a way that handles these exceptions gracefully and we can

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anticipate these.

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Sayres there's no such thing as a perfect program.

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However, we can try and do our best to learn from these errors and try to manage them so that our programs

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don't break.

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I'll see you in the next one.