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: Who played Lionel Hardcastle in the TV series 'As Time Goes By'?

Answer: as time goes by

Question: Who composed 'Eine Kleine Nachtmusik' in the 18th Century?

Answer: eine kleine nachtmusik

Question: Whose parents were Edmund Tudor and Margaret Beaufort?

Answer:
margaret beaufort