def __str__(self):
        exp = _repr(self.term)
        if isinstance(self.term, Expr) and self.priority < self.term.priority:
            exp = '(' + exp + ')'

        return self.exp + exp
dataset/ETHPy150Open pfnet/chainer/chainer/utils/type_check.py/UnaryOperator.__str__/swapped operands of `<`