Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.

Q: Who has taken over the TV role of Doctor Who, from actor David Tennant?

A: doctor who
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Q: Who was re-elected Prime Minister of Canada in May 2011?

A: prime minister of canada
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Q: Which river forms the boundary between Burma and Thailand?

A:
myanmar
****