We understand that there’s Washington, and there’s D.C. There are plenty of people who live and work in Washington, but not all of them know much about the District. So we’ve all been enjoying reading today’s article from the Post’s David Nakamura, in which he exposed that point through some hilarious interviews with some of D.C.’s Democratic superdelegates. There are 75 at-large superdelegates appointed by DNC Chair Howard Dean; 15 of them live in Washington,…