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- [Instuctor] In this self check

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we have two exercises for you.

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In the first case, we'd like
you to replace every occurrence

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of one or more tab characters
with a comma and a space.

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And in the second case we'd
like you to split the string

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that you see down below here.

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And we want you to do that
at any sequence of one

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or more adjacent $
characters in the string.

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So, go ahead and try those exercises

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and then come back to see the result.

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Okay, let's go ahead and
import the re module here,

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and here is the answer
to the first exercise.

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We're going to be replacing the tabs

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in the string with comma
and space characters,

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and here is the regular expression
that we're going to use.

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Notice the raw string literal

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because of the \ character here,

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so \t is the escape sequence
for a tab character,

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and we're saying that we are going

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to look for any sequence of
one or more tab characters,

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and replace them with comma spaces.

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So, we have one tab character,

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then we have two tab characters,

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then we have three tab characters.

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And when we execute that, you can see now,

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we have a uniformly formatted
comma delimited list

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with comma spaces separating each value

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in the string result.

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Now for the other exercise here,

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let's go ahead and reveal the answer.

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So again, we're splitting on one or more

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of the $ characters, so \$

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because $ is a regular
expression metacharacter.

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That was one of the characters
that was listed previously

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in the metacharacters
list that we showed you

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towards the beginning

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of the regular expressions presentation.

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And here again, + means one
or more, so we have one $,

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and we have two $, so when we split that

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we get '123', 'Main', and 'Street',

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as three separate strings
in the resulting list.