In the Simpsons episode "The Great Louse Detective" what's the end song a parody of?

Question

This episode is where Frank Grimes Jr. is trying to kill Homer. At the end, Sideshow Bob and Bart sing a song about 'growing accustomed to your face' and Homer bangs the wall and says to turn off that original cast recording. What original song is Sideshow parodying?

Answer 1

It is a song from the musical, "My Fair Lady". It is called "I've grown accustomed to her face".