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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 _add_stats_data(self, teams_list, team_data_dict):
 """ Add a team's stats row to a dictionary. Pass table contents and a stats dictionary of all teams to accumulate all stats for each team in a single variable. Parameters teams_list : generator A generator of all row items in a given table. team_data_dict : {str: {'data': str}} dictionary A dictionary where every key is the team's abbreviation and every value is another dictionary with a 'data' key which contains the string version of the row data for the matched team. Returns ------- dictionary An updated version of the team_data_dict with the passed table row information included. """

        for team_data in teams_list:
            if 'class="over_header thead"' in str(team_data) or\
               'class="thead"' in str(team_data):
                continue
            abbr = utils._parse_field(PARSING_SCHEME,
                                      team_data,
                                      'abbreviation')
            try:
                team_data_dict[abbr]['data'] += team_data
            except KeyError:
                team_data_dict[abbr] = {'data': team_data}
        return team_data_dict