Python3如何避免链式调用及lambda表达式换行时添加末尾反斜杠

共有两种常用的合规实现方式，均符合Python语法规范和PEP8编码要求：

• 方案1：用小括号包裹整个链式查询表达式
  Python语法允许括号（小/中/大括号）范围内的内容直接换行，无需额外添加反斜杠，是该场景下最常用的写法：

def select(self) -> any:
    with dict_session_scope() as local_session:
        word = None
        try:
            word = (
                local_session.query(Dict)
                .filter(Dict.demo_sentence == 0)
                .limit(5)
                .all()
            )
        except SQLAlchemyError as e:
            local_session.rollback()
            logger.error("query dict word error", e)
        finally:
            local_session.close()
        return word

• 方案2：拆分链式调用为中间变量
  如果需要实现动态查询（比如根据不同业务条件新增过滤规则、关联表逻辑），可以将每一步的查询对象单独赋值，逐步叠加：

def select(self) -> any:
    with dict_session_scope() as local_session:
        word = None
        try:
            query = local_session.query(Dict)
            # 此处可插入条件判断，动态新增查询规则
            query = query.filter(Dict.demo_sentence == 0)
            query = query.limit(5)
            word = query.all()
        except SQLAlchemyError as e:
            local_session.rollback()
            logger.error("query dict word error", e)
        finally:
            local_session.close()
        return word

内容的提问来源于stack exchange，提问作者Dolphin