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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 winning_abbr(self):
 """ Returns a ``string`` of the winning team's abbreviation, such as 'HOU' for the Houston Astros. """

        if self.winner == HOME:
            return utils._parse_abbreviation(self._home_name)
        return utils._parse_abbreviation(self._away_name)