#100DaysOfCode in Python Transcripts
Chapter: Days 25-27: Error handling
Lecture: Concepts: Error handling and exceptions
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Let's quickly review the concepts of try and except blocks in Python. Python's primary error handling style is what's called it's easier to ask
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for forgiveness than permission. As opposed to, say, C style of look before you leap. In C you check, check, check, check, check,
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and then you just try to do the thing and hope it works. Typically what happens when it doesn't work
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is either you get a false sort of return value there or just the program just goes away, it's really bad. Python is a little bit safer in that
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it's more carefully captures up the errors and converts them to exceptions. So if it's going to do that anyway, let's just try and make it work.
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And if it doesn't work, well, we'll catch it and deal with it in that case. So it's kind of an optimistic way of handling errors.
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so what we're going to do is we're going to say try and do all the stuff, and we're going to hope that it all just works
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and kind of assume that it will just go through that block. But if it doesn't, we're going to drop into one of the specific error handling sections.
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Here we have two possible errors, really one that we're dealing with, and the rest is kind of a catch all.
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So we're saying except connection error as CE, and then we're going to deal with that. And in this case we might need to look inside the error
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to see, well, was there a DNS problem, is there a network problem, did it not respond, things like that,
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did we get a 500 back from the server, all kinds of things. So this connection error, we're going to catch and deal with that
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and then we do this more general except block where here's something we maybe didn't think of, we're going to catch that and at
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least try to somewhat not crash. As we talked about before, the order matters. Most specific goes first, most general last.
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If you get that order wrong, you'll never get to your specific errors. So most specific, most general. This is error handling in Python.