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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 get_box_score(game_id):
 """Return the box score file of a game with matching 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.')