Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.

Q: What is the main river of Brazil?

A: brazil
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Q: Which Beatle played Youngman Grand in The Magic Christian 1969, with Peter Sellers?

A: the beatles
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Q: Who directed the first two Batman films that starred Michael Keaton?

A:
batman
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