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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 _list_backups_for_instance(self, instance, marker=0, limit=20):
 """ Instance-specific backups are handled through the instance manager, not the backup manager. """

        uri = "/%s/%s/backups?limit=%d&marker=%d" % (self.uri_base,
                                                     utils.get_id(instance),
                                                     int(limit),
                                                     int(marker))
        resp, resp_body = self.api.method_get(uri)
        mgr = self.api._backup_manager
        return [CloudDatabaseBackup(mgr, backup)
                for backup in resp_body.get("backups")]