Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.
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Question: a hospital ship is a big boat which is built to cure patients.

Answer: hospital ship


Question: anna stadling born 11 july 1970 in sundsvall, sweden is a swedish musical artist.

Answer: anna stadling


Question: pierre boulle (1912 - 1994) was a french writer.

Answer:
pierre boulle