def _get_player_stats_table(self, identifier):
        """Helper function for player season stats.

        :identifier: string identifying the type of stat, e.g. 'per_game'.
        :returns: A DataFrame of stats.
        """
        doc = self.get_sub_doc(identifier)
        table = doc('table#{}_stats'.format(identifier))
        df = sportsref.utils.parse_table(table)
        return df
Helper function for player season stats.

        :identifier: string identifying the type of stat, e.g. 'per_game'.
        :returns: A DataFrame of stats.