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 nationality of Chelsy Davy, former girlfriend of Prince Harry?

A: chelsy davy
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Q: Physics. What is the SI unit for amount of substance?

A: amount of substance
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Q: Who wrote the play 'Edward II'?

A:
edward ii
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