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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 postOptions(self):
 """ Delete the ports specified with the port-identifier option. """

        if self.portIdentifiers:
            store = self.parent.parent.getStore()
            store.transact(self._delete, store, self.portIdentifiers)
            print "Deleted."
            raise SystemExit(0)
        else:
            self.opt_help()