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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def fire(self, exclude=None, delay=True):
 """Notify everyone watching the event. We are explicit about sending notifications; we don't just key off creation signals, because the receiver of a ``post_save`` signal has no idea what just changed, so it doesn't know which notifications to send. Also, we could easily send mail accidentally: for instance, during tests. If we want implicit event firing, we can always register a signal handler that calls :meth:`fire()`. :arg exclude: If a saved user is passed in, that user will not be notified, though anonymous notifications having the same email address may still be sent. A sequence of users may also be passed in. :arg delay: If True (default), the event is handled asynchronously with Celery. This requires the pickle task serializer, which is no longer the default starting in Celery 4.0. If False, the event is processed immediately. """

        if delay:
            # Tasks don't receive the `self` arg implicitly.
            self._fire_task.apply_async(
                args=(self,),
                kwargs={'exclude': exclude},
                serializer='pickle')
        else:
            self._fire_task(self, exclude=exclude)