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: In March 1992 'Deeply Dippy' was the only number one hit for which group?

Answer: deeply dippy

Question: Aaron Copeland wrote a ballet about which American folk hero?

Answer: aaron copeland

Question: Which American invented the computer mouse whilst working at the Stamford Research Institute in 1964?

Answer:
computer mouse