Class variable inheritance

[HPJ]

> Makes sense to me. To step through what's happening:
>
> >>> A.n, B.n
> (0, 0)
>
> Here, the lookup on B.n fails (that is, B itself has no variable n),
> and thus falls back to A.n

See, this is what tripped me up, right at the beginning. I thought B
would inherit (as in copy) the variable n from A.

Can you point out to me which part (or parts) of the Language
Reference says this is the way it's supposed to be?