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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 deserialize_transactions(self, transactions=None, deserialize_only=None):
 """Deserializes the encrypted serialized model instances, tx, in a queryset of transactions. Note: each transaction instance contains encrypted JSON text that represents just ONE model instance. """


        if (
            not self.allow_self
            and transactions.filter(producer=socket.gethostname()).exists()
        ):
            raise TransactionDeserializerError(
                f"Not deserializing own transactions. Got "
                f"allow_self=False, hostname={socket.gethostname()}"
            )
        for transaction in transactions:
            json_text = self.aes_decrypt(cipher_text=transaction.tx)
            json_text = self.custom_parser(json_text)
            deserialized = next(self.deserialize(json_text=json_text))
            if not deserialize_only:
                if transaction.action == DELETE:
                    deserialized.object.delete()
                else:
                    self.save(obj=deserialized.object, m2m_data=deserialized.m2m_data)
                transaction.is_consumed = True
                transaction.save()