old_contents: # -*- coding: utf-8 -*-
  # © <YEAR(S)> <AUTHOR(S)>
  # License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
  
  from openerp import _, fields, models
  
  
  class SaleConfiguration(models.TransientModel):
      _inherit = 'sale.config.settings'
  
      freight_account_id = fields.Many2one(
          'account.account',
          string=_(u'Default account freight'),
      )
  
      installation_account_id = fields.Many2one(
          'account.account',
          string=_(u'Default account installation'),
      )
  
new_contents: # -*- coding: utf-8 -*-
  # © <YEAR(S)> <AUTHOR(S)>
  # License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
  
  from openerp import _, api, fields, models
  from openerp import SUPERUSER_ID
  
  
  class SaleConfiguration(models.TransientModel):
      _inherit = 'sale.config.settings'
  
      freight_account_id = fields.Many2one(
          'account.account',
          string=_(u'Default account freight'),
      )
  
      installation_account_id = fields.Many2one(
          'account.account',
          string=_(u'Default account installation'),
      )
  
      @api.v7
      def set_freight_account_id_defaults(self, cr, uid, ids, context=None):
          freight_account_id = self.browse(
              cr, uid, ids, context=context).freight_account_id
          res = self.pool.get('ir.values').set_default(
              cr, SUPERUSER_ID, 'sale.config.settings',
              'freight_account_id', freight_account_id.id)
          return res
  
      @api.v7
      def set_installation_account_id_defaults(self, cr, uid, ids, context=None):
          installation_account_id = self.browse(
              cr, uid, ids, context=context).installation_account_id
          res = self.pool.get('ir.values').set_default(
              cr, SUPERUSER_ID, 'sale.config.settings',
              'installation_account_id', installation_account_id.id)
          return res
  
subject: Add methods