German Krusty the Clown Show
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According to "In the Name of the Grandfather," at some point in the past, Krusty and Sideshow Mel shot episodes of "The Krusty the Clown Show" in German for German consumption.
This is a reference to a similar situation that occurred to the Monty Python troupe, who were compelled to create special German-language episodes of Monty Python's Flying Circus to clear German-specific content laws that were in force in West Germany at the time. The episodes were filmed at a Bavarian TV studio in German.