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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_variables_substitution_dictionaries(self, lhs_graph, rhs_graph):
 """ Looks for sub-isomorphisms of rhs into lhs :param lhs_graph: The graph to look sub-isomorphisms into (the bigger graph) :param rhs_graph: The smaller graph :return: The list of matching names """

        if not rhs_graph:
            return {}, {}, {}
        self.matching_code_container.add_graph_to_namespace(lhs_graph)
        self.matching_code_container.add_graph_to_namespace(rhs_graph)
        return self.__collect_variables_that_match_graph(lhs_graph, rhs_graph)