Why do researchers create AI systems that play games?

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Write an essay about game playing AI. Your essay should answer the following
questions.
1) Why do researchers create AI systems that play games?
To answer this question, explain how researchers justify the development of AIs
that play games.
2) What are THREE possible application areas for AI systems that play
games?
To answer this question, describe three possible application areas for gameplaying AI systems.
3) What do researchers think are the ethical problems with game-playing
AIs?
To answer this question, discuss the ethical aspects presented by researchers
about game playing AIs.
4) Are neural networks the best game players?
Based on what you have read, discuss this question, using evidence from the
literature.