如何在两个many2one字段中显示不同的显示名称？

class MyModel(models.Model):
    _name = 'my.model'

    field1 = fields.Many2one('related.model1', string='Field 1')
    field2 = fields.Many2one('related.model2', string='Field 2')

    @api.multi
    def name_get(self):
        result = []
        for record in self:
            name = ''
            if record.field1:
                name += record.field1.name
            if record.field2:
                name += ' - ' + record.field2.name
            result.append((record.id, name))
        return result