def from_miss(self, **kwargs):
        """Called to initialize an instance when it is not found in the cache.

        For example, if your CacheModel should pull data from the database to
        populate the cache,

            ...

            def from_miss(self, username):
                user = User.objects.get(username=username)
                self.email = user.email
                self.full_name = user.get_full_name()
        """

        raise type(self).Missing(type(self)(**kwargs).key())