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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 one(self):
 """ Return exactly one result or raise an exception. Raises fulfil_client.exc.NoResultFound if the query selects no rows. Raises fulfil_client.exc.MultipleResultsFound if multiple rows are found. """

        results = self.rpc_model.search_read(
            self.domain, 2, None, self._order_by, self.fields,
            context=self.context
        )
        if not results:
            raise fulfil_client.exc.NoResultFound
        if len(results) > 1:
            raise fulfil_client.exc.MultipleResultsFound
        return results[0]