Young, poverty-stricken, recluse American composer from the "Trouble in Tin Pan Alley" story of Fawcett comic book Whiz Comics #49 (December 1943).
Billy Batson of radio station WHIZ announces a patriotic song-writing contest. This young longhair stops work on his symphony just long enough to compose a stirring melody to win the contest and rent money. Captain Marvel himself collaborates with him to come up with the lyrics. And also fights off Nazi spies who want the tune for Germany!
His name is a parody of real Russian composer Dmitri Shostakovich (1906-1975).