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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 add_node_configuration(self, param_name, node_id, param_value):
 """ Set a parameter for a given node :param param_name: parameter identifier (as specified by the chosen model) :param node_id: node identifier :param param_value: parameter value """

        if param_name not in self.config['nodes']:
            self.config['nodes'][param_name] = {node_id: param_value}
        else:
            self.config['nodes'][param_name][node_id] = param_value