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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 _eval_model(self):
 """ Convenience method for evaluating the model with the current parameters :return: named tuple with results """

        arguments = self._x_grid.copy()
        arguments.update({param: param.value for param in self.model.params})
        return self.model(**key2str(arguments))