Question: What is the nationality of this novelist, short story writer, poet, screenwriter, and fighter pilot who wrote the novel that inspired the 1971 film "Willy Wonka & the Chocolate Factory?"
Sentence (from "Willy Wonka &amp; the Chocolate Factory"): Willy Wonka & the Chocolate Factory is a 1971 American musical fantasy film directed by Mel Stuart, and starring Gene Wilder as Willy Wonka.
Relevant evidence: Yes