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Alright, so let's talk about processing
nested lists. So we've got a list here

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called menu, containing eight lists. Each
of those lists contain items that make

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up the meals on the menu. In case you're
wondering why there's so much spam in

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these meals, the menu's based on a Monty
Python sketch. The Python programming

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language got its name, incidentally, from
Monty Python. Search the internet

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for Monty Python's Spam sketch and you can watch it
on YouTube when you feel like a break. That sketch,

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by the way, is also the reason we now
refer to junk emails as spam. Alright,

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so what we're going to do is run through
each of the meals, and try and find one

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that doesn't contain spam. So starting on
line 12, I'm going to type for meal

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in menu colon. Then I'm going to type if space
double quotes,  with spam in those double quotes,

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not in meal colon, print meal, in
parentheses. So it should print only the

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lists that don't contain spam. On the
screen there, you can see that's egg and

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bacon, and also egg, sausage and bacon.
Let's run the program to confirm that

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You can see that's the right output. Now
each of the items on the menu are

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themselves lists. Once you find one
without spam, you can print its items.

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Let's go ahead and do that, down
here, on line 16, and I'm going to come over here

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and I'm going to add for space item in
meal colon print and then item in parentheses.

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You'll often see nested loops used like this,
to process nested lists.

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Now we can also use the count
method, that sequence types have, to count

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how much spam is in each meal. So let's have
a go doing that, and to do that we need

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to add an else block, on line 18 over here;
else colon, then on line 19, print

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parentheses double quotes. We want zero
in left and right curly braces,

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has a spam score of, then 1 in left and right curly
braces. Press ENTER there,

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and type dot format on the next line,
parentheses meal comma meal.count

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parentheses double quotes, with the word
spam in those double quotes. We've got

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three right closing parentheses. Alright, so let's
run the program to see how much spam each meal contains.

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So just in case it wasn't obvious, you can use any

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expression in dot format. So on line 20,
we call the count method of the meal

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sequence, and it's the value that returns
that gets printed. That also shows how to

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use the count method, which means we've
now covered everything in that table of

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sequence operations. So let's briefly go back to that again,

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this one here. Alright, so time now for a
challenge. Let's go back to IntelliJ.

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We need a new file here. Let me take a copy of
these items - lines 1 to 10, inclusive.

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Then we need a new file.
I'm gonna call this one nospam.

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I'm gonna paste that code back in there.

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Alright, so let's talk about the
challenge.

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So we will go over a couple of
solutions to this, in the next video.