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ANA BELL: So we have
a list L, originally,

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[life, answer, 42, 0].

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In this example,
if you don't know

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Hitchhiker's Guide
to the Galaxy,

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that's why 42 is important.

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As a scientist, if I
didn't at least one example

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with the number 42, I'd
probably hear about it.

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So here it is.

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OK, so we have this
original list L,

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which contains the
string "life", the string

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"answer", the number
42, and the number 0.

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Here, I'm writing a loop that
iterates over every element

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directly in L, right?

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So originally, thing is going
to be string "life", then, thing

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is going to be the
string "answer", then,

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thing is going to
be the number 42.

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And so what am I doing inside
the loop as I'm iterating?

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Well, if thing is equal to
0, then I'm going to do this.

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And otherwise, I'm
going to do this.

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So for the first
two iterations when

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thing is equal to
"life" or "answer",

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I'm not doing anything.

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As soon as I hit 42 though,
I'm saying, L, at position 1,

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is going to get
this value here, OK?

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So when I've iterated over this
element here, I'm saying L,

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at position 1, I'm going to
change its value, which says,

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well, I'm going to
keep "life" the same,

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but this is going
to be "everything".

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And then we're keeping the
rest the same, 42 and 0,

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because we're only
modifying L at position 1.

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As soon as we do
that, we've finished

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with the loop when L was 42.

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And then we go through 0.

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So now, thing takes
on the value 0.

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And we say, if thing is equal
to 0, well, we're good on that.

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L, at position thing,
is equal to "universe".

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So L, at position 0,
is equal to "universe".

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So that says, OK, I'm going to
replace "life" with "universe".

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And then everything else
stays the same-- 42 and 0, OK?

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So that would be my answer,
[universe, everything, 42, 0].

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Great, that's the majority.

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Good job.