Quit 'farting around' [='messing around, fooling around'] and finish your work!
a cranky old 'fart'
(..) Hey, Jacques... I'm not Jacques. I am the Great Went. I am the Muffin. And what a muffin you've got, eh? I am as blank as a fart. Chug-a-lug, Donna. Yeah. I haven't seen you since I was thrown out of the One Eyed Jack's. What else did we do together? (..)1992 Twin Peaks: Fire Walk with Me