Pete Barbutti (the famous alumnus of Lisa's band camp) is an American comedian and musician. He made about 15 appearances on The Tonight Show Starring Johnny Carson and even had his own short-lived variety show called Pete's Place in the 1980's.
Near the start of the episode there is a cut to inside Homer's mind, in which familiar characters take roles based on emotions to parody the film Inside Out. Both the movie and this episode were 2015