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: spintronics is a kind of electronics that uses the tiny magnetic fields that come from electrons as well as their electric charge.

Answer: spintronics


Question: shaun of the dead is a 2004 british-french zombie-themed romantic comedy movie.

Answer: shaun of the dead


Question: control theory is an interdisciplinary branch of engineering and mathematics.

Answer:
control theory