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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 modify_parameters(self, modifier_function):
 """ Make modifications on the parameters of the legislation Call this function in `apply()` if the reform asks for legislation parameter modifications. :param modifier_function: A function that takes an object of type :any:`ParameterNode` and should return an object of the same type. """

        baseline_parameters = self.baseline.parameters
        baseline_parameters_copy = copy.deepcopy(baseline_parameters)
        reform_parameters = modifier_function(baseline_parameters_copy)
        if not isinstance(reform_parameters, ParameterNode):
            return ValueError(
                'modifier_function {} in module {} must return a ParameterNode'
                .format(modifier_function.__name__, modifier_function.__module__,)
                )
        self.parameters = reform_parameters
        self._parameters_at_instant_cache = {}