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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 save(self, banks_manager):
 """ Save all data from a banks_manager :param BanksManager banks_manager: BanksManager that your banks data will be persisted """

        self.banks_files.delete_all_banks()
        self.banks_files.save(banks_manager)
        self.index_file.save(banks_manager)