'Iterate the name and status of all services known to SystemD.'

def all_services(self):

    output = check_output(['systemctl', 'list-unit-files', '--no-legend'])
    for line in output.splitlines():
        line = line.rstrip()
        (service_name, service_status) = line.split(None, 1)
        (yield (service_name, service_status))
