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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def reward_explore(self):
 """ Add an exploration reward """

        if not 'explore' in self.mode:
            return
        mode = self.mode['explore']
        if mode and mode['reward'] and self.__test_cond(mode):
            self.player.stats['reward'] += mode['reward']
            self.player.stats['score'] += mode['reward']

            self.player.game_over = self.player.game_over or mode['terminal']