Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.
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Question: tricity is a big centre for tourism.

Answer: tricity

Question: ans is a municipality in the belgian province of liege.

Answer: ans

Question: johann bernoulli (6 august 1667 1 january 1748) was a swiss calvinist mathematician.

Answer:
johann bernoulli