def childgroup(self, field):
        """
        Return a list of fields stored by row regarding the configured grid

        :param field: The original field this widget is attached to
        """
        grid = getattr(self, "grid", None)
        named_grid = getattr(self, "named_grid", None)

        if grid is not None:
            childgroup = self._childgroup(field.children, grid)
        elif named_grid is not None:
            childgroup = self._childgroup_by_name(field.children, named_grid)
        else:
            raise AttributeError(u"Missing the grid or named_grid argument")

        return childgroup
Return a list of fields stored by row regarding the configured grid

        :param field: The original field this widget is attached to