Vampire Weekend producer and multi-instrumentalist Rostam Batmanglij studied classical music, but he hasn’t made a whole lot of it, at least not since he became famous. But Batmanglij did write five new instrumental pieces for the new revival of Kenneth Longeran’s 1996 play This Is Our Youth, which stars Michael Cera and Tavi Gevinson and which opens tomorrow at Broadway’s Cort Theater. (He also talked to the Associated Press a bit recently about the endeavor.) One of those pieces is a lovely, florid piano instrumental called “Upper West Side, 1982,” and you can listen to it at Pitchfork.