“I’m Still Here” from 1971’s Follies is a cultural road map of a musical number that name-checks an array of media darlings, fads, and politicos. It’s been performed by virtually every female entertainer of a certain age. Shirley MacLaine wrings every ounce of “been there, done that, and I’m not going anywhere” attitude she can from the showstopping number in a scene from the 1990 film version of Postcards From the Edge.