Gilmore Girls Related?

On Todays' ABC Family episode of Gilmore Girls (Say Goodnight,Gracie) there was a song playing and I really want to know the name of the song and artist. The song was playing while Jess was cleaning up the diner after they were closed and his dad comes in and they both sit down at the table. They both sing "ahhhhh, wham bam thank you ma'm" with the music. Can someone help me??