def disownServiceParent():
        """
        Use this API to remove an L{IService} from an L{IServiceCollection}.

        This method is used symmetrically with L{setServiceParent} in that it
        sets the C{parent} attribute on the child.

        @rtype: L{Deferred<defer.Deferred>}
        @return: a L{Deferred<defer.Deferred>} which is triggered when the
            service has finished shutting down. If shutting down is immediate,
            a value can be returned (usually, L{None}).
        """

        Use this API to remove an L{IService} from an L{IServiceCollection}.

        This method is used symmetrically with L{setServiceParent} in that it
        sets the C{parent} attribute on the child.

        @rtype: L{Deferred<defer.Deferred>}
        @return: a L{Deferred<defer.Deferred>} which is triggered when the
            service has finished shutting down. If shutting down is immediate,
            a value can be returned (usually, L{None}).
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/application/service.py