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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 _find_conferences(self, year):
 """ Retrieve the conferences and teams for the requested season. Find and retrieve all conferences for a given season and parse all of the teams that participated in the conference during that year. Conference information includes abbreviation and full name for the conference as well as the abbreviation and full name for each team in the conference. Parameters year : string A string of the requested year to pull conferences from. """

        if not year:
            year = utils._find_year_for_season('ncaaf')
        page = self._pull_conference_page(year)
        if not page:
            output = ("Can't pull requested conference page. Ensure the "
                      "following URL exists: %s" % (CONFERENCES_URL % year))
            raise ValueError(output)
        conferences = page('table#conferences tbody tr').items()
        for conference in conferences:
            conference_abbreviation = self._get_conference_id(conference)
            conference_name = conference('td[data-stat="conf_name"]').text()
            teams_dict = Conference(conference_abbreviation, year).teams
            conference_dict = {
                    'name': conference_name,
                    'teams': teams_dict
                }
            for team in teams_dict.keys():
                self._team_conference[team] = conference_abbreviation
            self._conferences[conference_abbreviation] = conference_dict