def _handle_start_nd(self, attrs):
        """
        Handle opening nd element

        :param attrs: Attributes of the element
        :type attrs: Dict
        """
        if isinstance(self.cur_relation_member, RelationWay):
            if self.cur_relation_member.geometry is None:
                self.cur_relation_member.geometry = []
            self.cur_relation_member.geometry.append(
                RelationWayGeometryValue(
                    lat=Decimal(attrs["lat"]),
                    lon=Decimal(attrs["lon"])
                )
            )
        else:
            try:
                node_ref = attrs['ref']
            except KeyError:
                raise ValueError("Unable to find required ref value.")
            self._curr['node_ids'].append(int(node_ref))
Handle opening nd element

        :param attrs: Attributes of the element
        :type attrs: Dict