def add_role(self, role, term, start_date=None, end_date=None,
                 **kwargs):
        """
        Examples:

        leg.add_role('member', term='2009', chamber='upper',
                     party='Republican', district='10th')
        """
        self['roles'].append(dict(role=role, term=term,
                                  start_date=start_date,
                                  end_date=end_date, **kwargs))