The head of comedy at the BBC said that the title had to include the word "Circus", because the people at the BBC had referred to the six cast members wandering around the BBC offices as a circus, so they added "Flying" to make it sound less like a real circus and more like something out of the first world war. And in front of that, added "Monty Python" because it sounded like a really bad theatrical agent, and also that the large, constricting snake was appropriate imagery.
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