A tuple key that uniquely describes this field.

        Used to compute this instance's hashcode and evaluate equality.

        Returns:
            Tuple[str]: The contents of this :class:`.RowRange`.

def _key(self):
        """A tuple key that uniquely describes this field.

        Used to compute this instance's hashcode and evaluate equality.

        Returns:
            Tuple[str]: The contents of this :class:`.RowRange`.
        """
        return (self.start_key, self.start_inclusive, self.end_key, self.end_inclusive)