[Python-ideas] Use `isinstance` check during exception handling

[Serhiy Storchaka]

On 05.11.15 00:02, sjoerdjob at sjec.nl wrote:
> Now, PEP3151 took over a year to be resolved, judging by the dates. If
> we have to go through changes like this more often, one will have to
> wait quite a while. Also, consider backwards compatibility issues. Code
> using FileNotFoundError will only run on Python3.3+.
>
> Thus I propose to have the exception handling code use the normal
> `isinstance` machinery, as it is more powerful, and allows one to use
> virtual base classes to check if the instance of the exception is
> relevant to catch. An example:
>
>      import errno
>
>      # Fake `FileNotFoundError` in Python3.2

Do you propose to add a new feature in 3.2?