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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 neutralize_variable(self, variable_name):
 """ Neutralizes an OpenFisca variable existing in the tax and benefit system. A neutralized variable always returns its default value when computed. Trying to set inputs for a neutralized variable has no effect except raising a warning. """

        self.variables[variable_name] = get_neutralized_variable(self.get_variable(variable_name))