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- [Instructor] In this and
the next several videos,

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we're going to be talking
about handling exceptions

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in Python.

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So far, when we've had
runtime problems in our code,

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we've simply seen tracebacks
appear either in Ipython

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or at the command line when we
were running a Python script.

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However it is possible to
write code that can look

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at problems that occur and
then deal with those problems.

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Now in the context of file processing,

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there happen to be a number
of potential exceptions

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that can occur.

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So, for example, if I
try to open up a file

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that does not exist, so that
I can read from that file,

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I'll wind up with a file not found error,

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or if I try to open a file for reading

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that's in a folder that
I don't have access to,

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or I try to write a file into a folder

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that I don't have access to,

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I'll get a permissions error.

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And if I try to write to a file object

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that's already been closed,

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I'll get a value error.

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So what we wanna do over
the next several videos

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is talk about how we can write code

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that's capable of dealing with exceptions.

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And we'll start by revisiting the concept

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of an exception in the first place,

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and then show you the code
that can be used to deal

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with problems as they occur.