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ANA BELL: I have
two functions here.

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One is add, and one is multiply.

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The add function returns
the sum of x plus y.

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And the multiply function just
prints the value of x times y,

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but doesn't return the value.

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Instead, it's going to
implicitly return none

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because we don't have any
return statement inside mult.

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So there are four lines here.

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And the question was how
many total lines of output

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will show up if
you run the code?

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OK, so how many lines
in the console show up?

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So when I do first
add 1, 2, it's

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going to go inside this function
here and say-- it says x is 1,

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y is 2, and return 3.

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So I'm replacing
this line with 3.

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But notice I'm never
printing it out.

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So this line of code will
not print out anything.

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Instead, the next line is
if I print add 2 plus 3,

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then I'm going to get 5.

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And I'm going to print that out.

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So that's one thing
I'm printing out.

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The next line says
multiply 3 and 4.

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So I'm going to go inside my
mult function and say, x is 3,

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y is 4.

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So I'm going to print 12
because 3 times 4 is 12.

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So that's another thing
that gets printed out.

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And I'm not doing anything
with the output-- or sorry, I'm

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not doing anything with
the return from mult.

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So that line is done.

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And the last one
is the trickiest

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and it says print mult 4 and 5.

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So first I'm going
to go in here.

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X is 4, y is 5.

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And I'm printing 20.

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So that's another print.

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And the return of this function
is going to be none, right?

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And the main thing here
is I'm going to print

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at the return of this function.

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So I'm also going
to print out none.

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So that's another one.

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So in total, I'm going to have
four different things printed

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out, the last one
being this none.