It's a song from the film "A Connecticut Yankee in King Arthur's Court" (1948), where it's sung by an unlikely trio, i.e. Bing Crosby, William Bendix, and Sir Cedric Hardwicke. Other verses: I've got to wake the sun up, he's li'ble to sleep all day; And then to ... the roses [?] so they'll be bright and gay; You must rehearse the songbirds, to see that they sing in key; Hustle bustle, and never a moment free. ... I told my friend the robin I'd buy him a brand new vest;Hustle, bustle, and never a moment's rest.

I'd like complete words of this myself; I've remembered it fondly [it has a very catchy tune] for nearly fifty years.