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: What is the only nation state of the Commonwealth of Nations on the mainland of South America?

Answer: commonwealth of nations

Question: Which country had a parliament called the Duma?

Answer: state duma

Question: What series of 29 British films made between 1958 and 1978 were made by a collection of actors including Sid James, Kenneth Williams, Charles Hawtrey, and Kenneth Connor?

Answer:
kenneth williams