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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 parent_org_sdo_ids(self):
        '''The SDO IDs of the compositions this RTC belongs to.'''
        return [sdo.get_owner()._narrow(SDOPackage.SDO).get_sdo_id() \
                for sdo in self._obj.get_organizations() if sdo]