def has_noquorum(self):
        """
        less than 1/3 of the known votes are on the same block
        """
        assert self.is_valid
        bhs = self.blockhashes()
        if not bhs or bhs[0][1] <= 1 / 3. * self.num_eligible_votes:
            assert not self.has_quorum_possible
            return True
less than 1/3 of the known votes are on the same block