code: def _game_image_from_screen(self, game_type):
          
          # screen
          screen_img = self._screen_shot()
          # game image
          game_rect = self._game_finders[game_type].locate_in(screen_img)
          if game_rect is None:
              return
          t, l, b, r = game_rect
          game_img = screen_img[t:b, l:r]
          return game_img
docs: Return the image of the given game type from the screen.
          Return None if no game is found.