def example_value(self):
        """
        If we're an instance of a Serializable, fall back to its
        `example_instance()` method.
        """
        from .serializable import Serializable
        inst = self._static_example_value()
        if inst is tr.Undefined and issubclass(self.klass, Serializable):
            return self.klass.example_instance()
        return inst
If we're an instance of a Serializable, fall back to its
        `example_instance()` method.