"The Act" by Kander and Ebb. It was a vehicle for Liza Minnelli, basically a one-woman show (with ensemble). It got awful reviews and is never revived, but Liza carried it--it made her a star.
I ask in all honesty/What would life be?/Without a song and a dance, what are we?/So I say "Thank you for the music/For giving it to me."