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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_item(self, item_type):
 """ Add a food collision reward """

        assert isinstance(item_type, str)

        if not 'items' in self.mode:
            return
        mode = self.mode['items']
        if mode and mode[item_type] and self.__test_cond(mode[item_type]):
            self.logger.debug("{item_type} consumed".format(item_type=item_type))
            self.player.stats['reward'] += mode[item_type]['reward']
            self.player.stats['score'] += mode[item_type]['reward']

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