Duparc introduced a two-player game for a function f between zero-dimensional Polish spaces in which Player II has a winning strategy iff f is of Baire class 1. We generalize this result by defining a game for an arbitrary function f : X → Y between arbitrary Polish spaces such that Player II has a winning strategy in this game iff f is of Baire class 1. Using the strategy of Player II, we reprove a result concerning first return recoverable functions.

中文翻译：

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以 BAIRE 1 类功能为特征的游戏

Duparc 为一项功能引入了两人游戏F在参与者 II 有一个获胜策略的 iff 零维波兰空间之间F是 Baie 类 1。我们通过为任意函数定义一个游戏来概括这个结果F：X → Y在任意波兰空间之间，使得玩家 II 在该游戏中具有获胜策略当且仅当F属于 Baie 类 1。使用 Player II 的策略，我们重新证明了有关第一次返回可恢复函数的结果。