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

Q: And Another Thing... by Eoin Colfer, published in 2009, eight years after the death of the author of the first five, is described as the sixth in which trilogy of books?

A: and another thing...
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Q: Chris Martin is the lead vocalist and rhythm guitarist with which group?

A: chris martin
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Q: Which American songwriter wrote the music and lyrics for the musical 'Annie get Your Gun'?

A:
annie get your gun
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