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- [Instructor] In this
self check exercise,

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we have a couple of
exercises for you to perform.

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In the first one, we
would like you to use a

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list comprehension, using the
techniques that you just saw

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in the preceding video, to
create a list of tuples,

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in which you'll have the numbers from one

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through five and their
corresponding cubes.

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So your list is going
to look something like

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what we show here, so one cubed is one,

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two cubed is eight, three cubed is 27.

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Now, we haven't of course
shown you creating tuples

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with a list comprehension
yet, so it is important

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to point out that in order
for you to create tuples,

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the expression to the
left of the for clause

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has to have parentheses
around it, and it would then

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contain a comma separated
list representing

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the elements that would
be placed into that tuple.

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Now for the other exercise,
we want you to use

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a list comprehension
and the range function,

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with a step this time, to create a list of

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the multiples of three
that are less than 30.

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So go ahead and pause the
video and give those a shot,

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and then come back to see the answers.

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Okay, let's go ahead and reveal the

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answer to this first exercise here.

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Now again, we're trying to create tuples

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based on the values in the
range one through five.

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So first, let's deal
with the range part here.

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For every item called X
in the range one up to

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but not including six,
so one through five,

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we're going to take that item, X,

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and place it into a tuple of
items, and the second element

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in that tuple is going
to be X's value cubed.

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So we give X and X cubed,
we wrap that in parentheses

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because that is required
when you're putting a tuple

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to the left of the for keyword
in a list comprehension,

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and if we then go ahead and
execute that and evaluate cubes,

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we can see that indeed, we get the tuples

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containing each value and
its corresponding cube.

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Now for the second exercise,
again we wanted to create

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a list of the multiples
of three less than 30,

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and we wanted to use a range
with a step to do that.

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So in this case, our for
clause uses the range three

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up to but not including 30,
counting by three each time.

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So for every value in that
range, we're simply going to

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include that value in our
list, and we simply name the

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target variable in order to
include that value in the list.

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So if I execute that cell
and then evaluate multiples,

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you can see we get all
the multiples of three,

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up to but not including 30.

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So the last one is 27 in this case.