code: def reward_wall(self):
          
          if not 'wall' in self.mode:
              return
          mode = self.mode['wall']
          if mode and mode and self.__test_cond(mode):
              self.logger.debug("Wall {x}/{y}'".format(x=self.bumped_x, y=self.bumped_y))
              self.player.stats['reward'] += mode['reward']
  
              self.player.game_over = self.player.game_over or mode['terminal']
docs: Add a wall collision reward