问在django的datatables中，外键值以对象而不是id的形式返回

EN

class UP_ROLE_MENU_MAP(models.Model):
    iRMID = models.AutoField(primary_key=True)
    iRoleID = models.ForeignKey(UP_ROLE_MASTER,on_delete=models.CASCADE,default='',db_column='iRoleID')
    iMenuID = models.ForeignKey(up_menus,on_delete=models.CASCADE,default='',db_column='iMenuID')
    iStatus = models.PositiveSmallIntegerField(default=1, blank=True,null=True)

class OrderListJson(BaseDatatableView):
    model = UP_ROLE_MENU_MAP
    columns = ['iMenuID', 'iDeleteAccess','iAddAccess','iViewAccess']
    order_columns = ['iMenuID', 'iDeleteAccess','iAddAccess','iViewAccess']
    max_display_length = 10
    def render_column(self, row, column):
        if column == 'iViewAccess':
            return ...
        else:
            return super(OrderListJson, self).render_column(row, column)