code: def get_box_score(game_id):
      
      year, month, day = get_date_from_game_id(game_id)
      try:
          return urlopen(GAME_URL.format(year, month, day, game_id,
                                         'boxscore.xml'))
      except HTTPError:
          raise ValueError('Could not find a game with that id.')
docs: Return the box score file of a game with matching id.