def getServiceNamed(name):
        """
        Get the child service with a given name.

        @type name: C{str}
        @rtype: L{IService}
        @raise KeyError: Raised if the service has no child with the
            given name.
        """

        Get the child service with a given name.

        @type name: C{str}
        @rtype: L{IService}
        @raise KeyError: Raised if the service has no child with the
            given name.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/application/service.py