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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 get_obstory_ids(self):
 """ Retrieve the IDs of all obstorys. :return: A list of obstory IDs for all obstorys """

        self.con.execute('SELECT publicId FROM archive_observatories;')
        return map(lambda row: row['publicId'], self.con.fetchall())