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

Q: The Byzantine Empire is the term used since the 19th century to describe the Roman Empire of the Middle Ages, centred on its capital, where?

A: byzantine empire
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Q: Which play and film was adapted from a story by Christopher Isherwood and later adapted as the musical and film Cabaret?

A: cabaret
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Q: The Dakar Rally (previously known as the Paris Dakar rally) is an annual event, but of which country is Dakar the capital city?

A:
dakar
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