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- [Narrator] In this self check exercise,

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we'd like you to take
the string 10 plus five

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that represents an addition problem,

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and use a regular expression

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to break that string into
three pieces of information

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representing the two operands

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and the plus operator in between,

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and then to display those
pieces of information as well.

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So go ahead and pause the video,

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give it a shot,

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and then come back to see the answer.

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

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as we always need to do here,

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and this is the regular expression search

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that we're performing.

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You can see we have a raw string literal

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in which we're looking for a subexpression

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that we're going to capture,

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which consists of one or
more digit characters.

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Then we have a space

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and another sub string that
we're going to capture,

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and in this case we created
a custom character class,

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looking for the arithmetic
operator characters

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minus, plus, times, and divide.

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And then we have another space.

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And then finally we have another digit,

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one or more digits,

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that we would like to capture.

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So we have three subexpressions
that we want to capture,

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and we're going to be trying to match

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those inside of the string 10 plus five.

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Now of course,

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we specifically wrote this out

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to match up with that
string on purpose here,

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so let's go ahead an execute that.

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Now, let me expand these
others snippets here.

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So if you want to see all of the matches,

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remember you can call the
groups method to do that,

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so you can see we
matched three substrings,

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and of course,

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once we have those substrings,

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we could do things like convert these

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into actual numeric values

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and use them in a real
arithmetic operation

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if we wanted to.

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Down below here,

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we want to just also show you

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that you can individually
access each of those,

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so let's just go ahead and do that,

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and you can see again,

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starting from index number one,

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not index zero,

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you can get the values that were captured

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by the three subexpressions

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in the original, regular expression.