def handle_label_relation(self, line: str, position: int, tokens: ParseResults) -> ParseResults:
        """Handle statements like ``p(X) label "Label for X"``.

        :raises: RelabelWarning
        """
        subject_node_dsl = self.ensure_node(tokens[SUBJECT])
        description = tokens[OBJECT]

        if self.graph.has_node_description(subject_node_dsl):
            raise RelabelWarning(
                line_number=self.get_line_number(),
                line=line,
                position=position,
                node=self.graph.node,
                old_label=self.graph.get_node_description(subject_node_dsl),
                new_label=description
            )

        self.graph.set_node_description(subject_node_dsl, description)
        return tokens
Handle statements like ``p(X) label "Label for X"``.

        :raises: RelabelWarning