In film Gold Diggers Of 1935; Academy Award for Best Song, Harry Warren's first of three. The other two were You'll Never Know and On The Atchison, Topeka And The Santa Fe. No connection with the Gold Diggers Of Broadway film made in 1929. See: Tiptoe Through The Tulips.
Based on a theme from Brahms' Hungarian Dances and on the Barcarolle from Les Contes d'Hoffmann (see there).