 At least two sketches can trace their origins back to  _How to Irritate People (1968) (TV)_ (qv), a TV special that  John Cleese (qv) starred in and wrote with Graham Chapman (qv)  prior to "Flying Circus". First, the "Silly Job Interview" in which  Cleese rings a bell and has people scoring Chapmans reaction came  directly from the special. Also the infamous/famous "Parrot Sketch"  was adapted largely from a sketch Chapman wrote for the earlier show  about a car salesman who flatly refused to admit that there was  anything wrong with the car that was literally falling apart on  stage.