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

Q: Which engineer built the Menai Suspension Bridge and the Caledonian Canal?

A: menai suspension bridge
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Q: What is the name of the astromech droid companion of Anakin Skywalker, Luke Skywalker and Obi-Wan Kenobi in the Star Wars franchise?

A: droid
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Q: Who was the trainer of the 2010 Grand National winning horse Don't Push It?

A:
don't push it
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