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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 set_replace_results(self, replace_results):
 """ Sets the Model Nodes using given replace results. :param replace_results: Replace results. :type replace_results: list :return: Method success. :rtype: bool """


        root_node = umbra.ui.nodes.DefaultNode(name="InvisibleRootNode")
        for file, metrics in sorted(replace_results.iteritems()):
            replace_result_node = ReplaceResultNode(name=self.__format_replace_metrics(file, metrics),
                                                    parent=root_node,
                                                    file=file)
        self.__model.initialize_model(root_node)
        return True