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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_officials(self):
 """ Parse the officials :returns: ``self`` on success, ``None`` otherwise """

        # begin proper body of method
        lx_doc = self.html_doc()
        off_parser = opm(self.game_key.season)
        self.officials = off_parser(lx_doc)

        return self if self.officials else None