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Instructor: Welcome back.

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One of the common patterns when working with files

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is to actually put them in a try accept block.

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So in here we can say, try

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and actually put them like this

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and try out to see if the file exists.

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So we can say except and let's say

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FileNotFoundError, which we've seen before.

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And here I can say as err

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and inside we'll say print

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file does not exist.

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So that now if I run this,

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and remember in our current directory

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we don't have sad.text.

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If I run this,

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I get an error file does not exist.

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We can even raise this error if we wanted to.

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So we can say raise err.

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So now it works as expected

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I'll get file does not exist

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and then give a FileNotFoundError.

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So this is a common way to work with files

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to handle different errors.

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Another common one with files

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is this idea of an IOError

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and an IOError usually happens when the computer

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or the machine you're on has some issue reading or writing

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or doing any sort of IO operation.

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So you can have something like IO Error in here

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and raise that error if you want.

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Again, if I run this FileNotFoundError

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if for some reason I give it a weird mode to do

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I get an unsupported operation error.

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The options are endless

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but I hope by now you have an idea of how to do file IO.

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But let's do a fun exercise because up until now

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we haven't really done anything exciting.

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We just read a bunch of texts from a file and that was it.

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Nothing that creative, right?

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So let's do something fun.

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In the next video we're gonna try and build a translator.

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That's right, I'll see you in the next video.

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Bye bye.