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

Q: What is the only nation state of the Commonwealth of Nations on the mainland of South America?

A: commonwealth of nations
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Q: What was the computer's name in 2001: A Space Odyssey?

A: 2001: a space odyssey
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Q: Which artist had a 'Blue Period' from 1901 to 1904 and a 'Rose Period' from 1904 to 1906?

A:
picasso's rose period
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