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- [Instructor] In this
self check exercise,

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we have a couple of different problems

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that we'd like you to attack.

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First, we want you to create
a tuple called high-low

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that represents a day of the
week, along with the high

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and the low temperature
as integers for that day.

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And we'd like you to display
its string representation

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and then perform these two
tasks using that high-low tuple.

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First, we want you to access
each of the individual values

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in that tuple via index numbers

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and display the element values.

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And then, we want you to unpack that tuple

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into just the variables Day and High,

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and show what happens and explain
why that happens, as well.

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In the second exercise, we
want you to create a list

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of names containing three name
strings, and then enumerate

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those values using the
enumerate function so that you

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can display each element's
index and corresponding value.

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So go ahead and pause this video,

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take a shot at the two exercises
you see here on the screen,

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and then come back to see the answers.

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Okay, let's go ahead and
reveal the answer here

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for this first exercise.

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So again, initially we're
going to create the tuple

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called high-low, and we'll
stick into that a name of a day

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and a couple of integer
values representing the high

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and low temperatures, respectively.

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So let me go ahead and execute that.

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And to display its string
representation, we can simply

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evaluate the variable.

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So here is that string representation.

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Now in Part A up above, we
said we wanted you to use

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the square brackets
operator and index numbers

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to access each of the three
pieces of information.

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So here, we're going to
produce a formatted string,

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in which the first
placeholder is going to access

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element zero of the
tuple, which is the day.

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The second placeholder is
going to access element one

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of the tuple, which is
the high temperature.

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And the last is going to
access the low temperature

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within that tuple.

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So let's just display that
and we can see that, indeed,

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we were able to pick off
each of those elements.

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Now, you may recall from the
preceding couple of videos

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that, when you're unpacking a
tuple or any other sequence,

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the left side of the assignment
must have the appropriate

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number of variables to match
up with the total number

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of elements within that sequence.

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So in this piece of the
exercise, we asked you to unpack

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a three-element tuple into
a set of two variables,

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Day and High.

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And if I execute that, you
can see here that we wind

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up with a value error:
too many values to unpack.

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So Python is going to check
the length of the sequence

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on the right side,

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make sure it matches up
with the number of variables

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on the left side, and in
this case it does not.

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There are too few
variables on the left side,

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and thus, too many values to
stuff into those variables.

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And therefore, we get an
error in this particular case.

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In this last, minimize
things just the answer

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saying that we have to
have enough variables

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to unpack the corresponding elements.

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Now in this second exercise,
we wanted you to create a list

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of names with three strings
and then use a for loop

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and the enumerate function
to iterate over those values

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and display their indices and values.

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So here we have a string--

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a list, excuse me, containing
three string names.

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And let's go ahead and iterate over that

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with the enumerate function.

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So Names is the list to enumerate over.

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We're going to wind up with
a sequence of three tuples:

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zero in Amanda, one in Sam, two in David.

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We're going to unpack those
tuples into I for the index

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number and Name for the name.

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And we'll simply then display
those values line by line

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after the cell here.