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- [Instructor] For this
Self Check exercise,

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we'd like you to work with
a couple of the functions

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that we just presented
in the preceding video.

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First, we'd like you to play around

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with the min function,
both with and without

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the second argument, the key argument.

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So we'd like you to create
a list called foods,

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containing the strings that you see here.

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And I've already put that statement

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in the notebook here for you to look at.

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Then what we want you to do is call the

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min function with this list as is.

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And in a second statement, we want you

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to call the min function with the

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strings, such that you can ignore

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the case for finding the minimum.

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So we did that in the preceding video

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by calling the lower
function, or method, rather,

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on each of the strings in the list

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as part of calling the min function.

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So that's one exercise.

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And then separately, we would like you

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to use the zip function,
that we just introduced,

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to zip together two integer
lists and create a new list

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containing the sum of the elements

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from the corresponding
indices in both lists.

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So elements at position zero in each list

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will be added together,
elements at position one

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in each list will be added
together, et cetera, et cetera.

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And you can do that a
number of different ways.

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In the solution, I'll show you,

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we'll use a list comprehension.

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But go ahead and give that a shot

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and then come back to see the results.

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OK, let's take a look at the
first exercise up above here.

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And again, we're going to create the list

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first, so I'll go ahead and do that.

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Now the first thing we wanted you to do

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was try the min function
with the list as is.

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So don't worry about the
uppercase-lowercase sensitivity.

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And based on uppercase, lowercase, again,

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the uppercase letters are going
to have the smallest values,

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so Bacon should be the
minimum in this case.

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And indeed, it is.

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However, if you want to do a
case-insensitive comparison,

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you have that capability by
providing that keyword argument.

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So in this case, once again, we're saying

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for each string, give
me the lowercase string

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and use those lowercase strings

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to figure out the minimum value in foods.

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And, as you can see, apples is

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the minimum value in that case.

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And of course, we did
get different results.

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And the reason for that, once again,

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is that in the first
case, we're doing a pure

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lexicographical comparison and we're not

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specifying how to modify those elements

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for the purpose of comparison.

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In the second case, we are saying only

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look at these strings as
all lowercase letters,

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and therefore, we got the case-insensitive

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comparison in that example.

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And apples came out smallest in that case.

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Now as far as zipping goes,
here is a zip solution

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for a couple of sequences of integers.

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In this case, two lists of integers,

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one containing 10, 20, and 30,

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and one containing one, two, and three.

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And of course, we can define those

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and assign them to variables.

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And they don't have to be lists.

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They could be other sequences,
such as tuples, et cetera.

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So what we're going to do is zip together

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the pairs of elements from those,

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so 10 and one will be zipped together,

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20 and two will be zipped together,

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and 30 and three will be zipped together.

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For each tuple, as we
iterate through them,

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we will unpack the
tuple into the variables

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a and b, and then, in the resulting list,

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we will add a and b together
to produce the list element.

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So if I go ahead and execute that,

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we can see we get 11,
which is 10 plus one,

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22, for 20 plus two,

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and 33 for 30 plus 3.