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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(self, item: SQLBaseObject):
 """Puts a item into the database. Updates lastUpdate column"""

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