'The base class invokes this method to notify the implementation to
register the file descriptor with the polling object. The request must
be ignored if the poller is not activated.
:param int fileno: The file descriptor
:param int events: The event mask using READ, WRITE, ERROR'

def _register_fd(self, fileno, events):

    self._modify_fd_events(fileno, events=events, events_to_clear=0, events_to_set=events)
