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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 _put_many(self, items: Iterable[DtoObject], cls):
 """Puts many items into the database. Updates lastUpdate column for each of them"""

        if cls._dto_type in self._expirations and self._expirations[cls._dto_type] == 0:
            # The expiration time has been set to 0 -> shoud not be cached
            return
        session = self._session
        for item in items:
            item = cls(**item)
            item.updated()
            session.merge(item)