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

Q: Who has written a series of novels, entitled The Dark Tower, of which the first, in 1982, was entitled, The Gunslinger?

A: the dark tower
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Q: Ewart was the middle name of which British Prime Minister?

A: prime minister of the united kingdom
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Q: Who plays architect Doug Roberts in the 1974 film 'Towering Inferno'?

A:
doug roberts
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