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Alright, so how did you get on? Did you spot
the places in escapechar.py

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where the code doesn't conform to the style
guide? Well, the three problems are with

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the names of our variables. Now, if we go and
scroll up and look on line one up here,

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I used camel case for the name split
String.That's the convention in Java, for

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example, but we should avoid doing that
in Python.

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It's called camel case, by the way,
because the large capital letters

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resemble the humps of a camel. Camel case
reflects the shape of the word, when you

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include capitals in it.
Alright so that's the first one.

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The next is tabbedString on line 4, and the
third one is anotherString down

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on line 14. Now those three variables
appear on six lines of the code; lines 1

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& 2, again on lines 4 & 5, and lines 14
and 19. Now it wouldn't be too hard to

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change them in this short program, but in
a larger program they could be appearing

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all over the place.
If you forgot to change one of them, or

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made a typing error, you'd cause an error
in the code. And that's not good, and it's why

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you shouldn't refactor code just to
conform to a style guide. But I'm gonna

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break that rule here, because I want to
show you how your IDE can make that a

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lot easier and safer. What we're going to
do is refactor the code, to make it

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comply with PEP 8. Refactoring code means
changing its structure, without changing

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its behavior.
Refactoring might change how the code

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does things, but it doesn't change what it does.

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Alright, so in IntelliJ and PyCharm, I
can right click on splitString and I'm

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going to do that on line one. So from the
context menu that appears, I'm going to

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choose Refactor, then Rename. As you can
see, that popped up a dialog where we can

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change the name of the variable. I'm
gonna change it to conform to the

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guidelines; split_string,
instead of a capital S like we had.

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Click on the Refactor button, and all
occurrences of splitString are renamed.

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We can see, in this case, it's been changed on
lines 1 & 2. I'm going to do the same for

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tabbedString on line 4. That should be
tabbed_string.

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Then we're gonna do the same again for
anotherString, right click, Refactor,

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Rename, and that, of course, should be
another_split_string

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I say, of course, but you get
the jist there. Okay, so there's the 3

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things changed, and you can see that both
lines 14 and line 19 are changed there.

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Now most modern IDEs have a feature that
allows you to rename things in your code,

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and that's much safer than doing it
manually. As I said, if you miss one or

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make a typing error, you'll break
the code. Make sure you test your code

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after refactoring it. Run the program to
make sure it still works.

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Alright so the code in this course
will follow the PEP 8 guidelines, most of

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the time. I'm re-recording the videos
for this course, and some of the earlier

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examples were written a long time ago.
You might find that some of them don't

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follow PEP 8.
You'll also find code in the Python

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libraries, and elsewhere, that doesn't
follow those guidelines either. The code

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that you write should follow the
guidelines, and I'll refer you back to

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them, as we cover various new Python
features. Now there's one more thing that

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I want to cover, and we'll look at that
in the next video.