An answer is given. Generate a question for which the given answer is either a direct or partial answer.
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Question: Answer: marcus atilius regulus

Answer: who was the commander of the first punic war?


Question: Answer: river shannon

Answer: what is the most famous and longest river in ireland?


Question: Answer: tokyo, japan

Answer:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
what is the most crowded city in asia?


