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ANA BELL: All right, so let's see.
So first we have L1 is equal to bacon, eggs.
I'm going to short form-- shorthand this.
L2 is equal to toast and jam.
Brunch-- I should actually make these arrows-- brunch
is equal to L1.
So this is just aliasing, which means
brunch is going to point to whatever L1 object points to.
And if I do L1.append juice, L1 is now
going to be bacon, eggs, and juice.
OK?
This L1 has been mutated to be that.
And since brunch still points to the same object
that L1 points to, brunch is now going to point to there.
OK?
So when I do brunch.extend L2, I'm
going to take whatever brunch is, which is this part here,
and I'm going to extend it by L2, which is toast and jam.
OK?
So it's just going to contain a large list of those five
elements because of this side effect issue, where
brunch was pointing to the same thing
that L1 was pointing to, OK?
So it's close, but I think-- perfect.
Yes, that's the right answer.