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From: Chris Angelico <rosuav@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: Python Error message
Date: Fri, 5 Aug 2016 05:53:29 +1000
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On Fri, Aug 5, 2016 at 5:36 AM, Terry Reedy <tjreedy@udel.edu> wrote:
> An example of the latter is when one writes code in Python to execute
> 'other' code.  (IDLE is one example.  It both executes user statements and
> evals user expressions.)  One needs "except BaseException:"  to isolate the
> interpreter from exceptions raised in the interpreted code. (It would be
> wrong for IDLE to stop because a user submitted code that raises, whether
> intentionally or accidentally)  A 'raise' that throws the exception into the
> interpreter is likely the worst thing to do.

This is a classic example of a "boundary location". Another extremely
common example is a web server: if an exception bubbles out of a
request handler function, the outer wrapper code should catch that,
log it, and send a 500 back to the client.

But none of this is what the OP is doing.

ChrisA