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: Which musical has the songs 'Another Suitcase In Another Hall' and 'Oh What A Circus'?

Answer: another suitcase in another hall


Question: Eden Park staged some of the 2011 Rugby World Cup matches, in which city can it be found?

Answer: eden park


Question: In which BBC crime drama which ran for six series, did clinical psychologist 'Dr. Tony Hill' work first with 'DI Carol Jordan' and then with 'DI Alex Fielding'?

Answer:
dr. tony hill