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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 _parse_opponent_abbr(self, game_data):
 """ Parses the opponent's abbreviation for the game. The opponent's 3-letter abbreviation is embedded within the HTML tag and needs a special parsing scheme in order to be extracted. Parameters game_data : PyQuery object A PyQuery object containing the information specific to a game. """

        opponent = game_data('td[data-stat="opp_name"]:first')
        opponent = re.sub(r'.*/teams/', '', str(opponent))
        opponent = re.sub(r'\/.*.html.*', '', opponent)
        setattr(self, '_opponent_abbr', opponent)