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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 get_model(self):
 """ Return the class Model used by this Agnocomplete """

        if hasattr(self, 'model') and self.model:
            return self.model
        # Give me a "none" queryset
        try:
            none = self.get_queryset().none()
            return none.model
        except Exception:
            raise ImproperlyConfigured(
                "Integrator: Unable to determine the model with this queryset."
                " Please add a `model` property")