Negates the current state for this query.
        
        :return     <self>

def negated(self):
        """
        Negates the current state for this query.
        
        :return     <self>
        """
        query = self.copy()
        op = self.op()
        query.setOp(self.NegatedOp.get(op, op))
        query.setValue(self.value())
        return query