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 1970s musical film starred Angela Lansbury as a trainee witch?

Answer: angela lansbury


Question: Which country mainly makes up the Horn of Africa?

Answer: africa


Question: Who is the father of the twin boys born to Brooke Mueller on 14 March 2009?

Answer:
brooke mueller