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: The plays 'The Barber of Seville' and 'Marriage of Figaro' were written by whom?

Answer: the marriage of figaro


Question: What was the first British credit card?

Answer: credit card


Question: The 66 mile long Shropshire Union Canal links the city of Wolverhampton to which town situated in Cheshire?

Answer:
cheshire