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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 notify(self, instance=None, **kwargs):
 """A wrapper to call notification.notify for each notification class associated with the given model instance. including only notifications sent. """

        notified = {}
        for notification_cls in self.registry.values():
            notification = notification_cls()
            if notification.notify(instance=instance, **kwargs):
                notified.update({notification_cls.name: instance._meta.label_lower})
        return notified