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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 populate(self, deserialized_txs=None, filename=None, retry=None):
 """Populates the batch with unsaved model instances from a generator of deserialized objects. """

        if not deserialized_txs:
            raise BatchError("Failed to populate batch. There are no objects to add.")
        self.filename = filename
        if not self.filename:
            raise BatchError("Invalid filename. Got None")
        try:
            for deserialized_tx in deserialized_txs:
                self.peek(deserialized_tx)
                self.objects.append(deserialized_tx.object)
                break
            for deserialized_tx in deserialized_txs:
                self.objects.append(deserialized_tx.object)
        except DeserializationError as e:
            raise BatchDeserializationError(e) from e
        except JSONFileError as e:
            raise BatchDeserializationError(e) from e