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: 'Edward Lewis' and 'Vivian Ward' were the principal characters in which popular 1990 film?

Answer: edward lewis


Question: Who sang the theme tune to the James Bond film Die Another Day?

Answer: die another day


Question: Who is the protagonist and narrator of Robert Louis Stevenson's novels 'Kidnapped' and 'Catriona'?

Answer:
robert louis stevenson