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

Answer: eden park


Question: Which horse won the 2008 Grand National?

Answer: 2008 grand national


Question: David Gest, a concert promoter, was the fourth husband of whom from March 2002 until their divorce in April 2007?

Answer:
david gest