BaseSelectorEventLoop.close() now closes the self-pipe before calling the parent close() method. If the event loop is already closed, the self-pipe is not unregistered from the selector.
BaseSelectorEventLoop.close() now closes the self-pipe before calling the
parent close() method. If the event loop is already closed, the self-pipe is
not unregistered from the selector.

overcastcloud/trollius,overcastcloud/trollius,overcastcloud/trollius