Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
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Question: The film The Curious Case of Benjamin Button, starring Brad Pitt, is based on a short story by whom?

Answer: the curious case of benjamin button


Question: Which was the title of the 7th and final book in the Chronicles of Narnia by C.S. Lewis?

Answer: the chronicles of narnia


Question: Which group had a number one hit for two weeks in 1961 with 'Blue Moon'?

Answer:
blue moon