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

Q: Allopurinol is typically prescribed for which illness?

A: allopurinol
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Q: Double vision, the perception of two images from a single object, is properly called what?

A: double vision
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Q: Which author created the characters 'Veruca Salt', 'Augustus Sloop' and 'Arthur Slugworth'?

A:
charlie and the chocolate factory
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