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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_node_list(self):
 """Get the list of Node instances. This method returns the list of Node instances composing the graph. """

        node_objs = list()

        for obj_dict_list in self.obj_dict['nodes'].values():
            node_objs.extend([
                Node(obj_dict=obj_d)
                for obj_d
                in obj_dict_list])

        return node_objs