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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 import_batch(self, filename):
 """Imports the batch of outgoing transactions into model IncomingTransaction. """

        batch = self.batch_cls()
        json_file = self.json_file_cls(name=filename, path=self.path)
        try:
            deserialized_txs = json_file.deserialized_objects
        except JSONFileError as e:
            raise TransactionImporterError(e) from e
        try:
            batch.populate(deserialized_txs=deserialized_txs, filename=json_file.name)
        except (
            BatchDeserializationError,
            InvalidBatchSequence,
            BatchAlreadyProcessed,
        ) as e:
            raise TransactionImporterError(e) from e
        batch.save()
        batch.update_history()
        return batch