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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_variables(self, tax_benefit_system):
 """ Neutralizing input variables not in input dataframe and keep some crucial variables """

        for variable_name, variable in tax_benefit_system.variables.items():
            if variable.formulas:
                continue
            if self.used_as_input_variables and (variable_name in self.used_as_input_variables):
                continue
            if self.non_neutralizable_variables and (variable_name in self.non_neutralizable_variables):
                continue
            if self.weight_column_name_by_entity and (variable_name in self.weight_column_name_by_entity.values()):
                continue

            tax_benefit_system.neutralize_variable(variable_name)