Question: Which American actor, screenwriter, director, producer, singer-songwriter and author sang this song from the 1971 movie "Willy Wonka & the Chocolate Factory" that was written by British composers Leslie Bricusse and Anthony Newley?
Sentence (from "Pure Imagination"): The intro of the song, which also is the musical code for entering the Chocolate Room played by Willy Wonka, is the introduction of Wolfgang Amadeus Mozart's "Marriage of Figaro".
Relevant evidence: No