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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 add_results(self, *rvs, **kwargs):
 """ Changes the state to reflect the mutation which yielded the given result. In order to use the result, the `fetch_mutation_tokens` option must have been specified in the connection string, _and_ the result must have been successful. :param rvs: One or more :class:`~.OperationResult` which have been returned from mutations :param quiet: Suppress errors if one of the results does not contain a convertible state. :return: `True` if the result was valid and added, `False` if not added (and `quiet` was specified :raise: :exc:`~.MissingTokenError` if `result` does not contain a valid token """

        if not rvs:
            raise MissingTokenError.pyexc(message='No results passed')
        for rv in rvs:
            mi = rv._mutinfo
            if not mi:
                if kwargs.get('quiet'):
                    return False
                raise MissingTokenError.pyexc(
                    message='Result does not contain token')
            self._add_scanvec(mi)
        return True