A modified TaxBenefitSystem
All reforms must subclass Reform and implement a method apply().
In this method, the reform can add or replace variables and call modify_parameters to modify the parameters of the legislation.
Example:
>>> from openfisca_core import reforms >>> from openfisca_core.parameters import load_parameter_file >>> >>> def modify_my_parameters(parameters): >>> # Add new parameters >>> new_parameters = load_parameter_file(name='reform_name', file_path='path_to_yaml_file.yaml') >>> parameters.add_child('reform_name', new_parameters) >>> >>> # Update a value >>> parameters.taxes.some_tax.some_param.update(period=some_period, value=1000.0) >>> >>> return parameters >>> >>> class MyReform(reforms.Reform): >>> def apply(self): >>> self.add_variable(some_variable) >>> self.update_variable(some_other_variable) >>> self.modify_parameters(modifier_function = modify_my_parameters)
Make modifications on the parameters of the legislation.
Call this function in apply() if the reform asks for legislation parameter modifications.
modifier_function – A function that takes a ParameterNode
and should return an object of the same type.