这里说的上层调用处理？这句话如何理解呢？

Question

Answer 1

文章后面有举例，上层调用指的就是外层的代码(外层的try catch)。raise会将错误信息抛出给外层，然后外层try catch捕捉到异常后处理。

Answer 2

好比这样

def outter():
    try:
        inner()
    except IOError:
        #do something
    finally:
        #do something

def inner():
    try:
        #do something
    except IOError:
        raise
    finally:
        #do something

if __name__ == '__main__':
    out()