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: Who painted The Card Players, at Feb 2012 the most expensive artwork in the world?

Answer: the card players


Question: The headquarters building of which government agency is known as 'The Doughnut' due to its shape?

Answer: the doughnut


Question: Who was the last president of Czechoslovakia before its dissolution in 1993?

Answer:
czechoslovakia