'An atexit handler which asserts the Bus is not running.'

def _clean_exit(self):

    if (self.state != states.EXITING):
        warnings.warn(('The    main    thread    is    exiting,    but    the    Bus    is    in    the    %r    state;    shutting    it    down    automatically    now.    You    must    either    call    bus.block()    after    start(),    or    call    bus.exit()    before    the    main    thread    exits.' % self.state), RuntimeWarning)
        self.exit()
