Highlight error location in the technical 500 debug page on Python 3.11+.

[Adam Johnson]

Similar to these tickets for extending the debug page for Python 3.11 exception changes: #33747, #33752.

Python 3.11 adds "where in the line" highlighting to tracebacks:

$ python3.11 t.py
Traceback (most recent call last):
  File "/.../example.py", line 5, in <module>
    formula(1, 0)
    ^^^^^^^^^^^^^
  File "/.../example.py", line 2, in formula
    return a / b + b / a
           ~~^~~
ZeroDivisionError: division by zero

Release note: ​https://docs.python.org/3.11/whatsnew/3.11.html#enhanced-error-locations-in-tracebacks

It would be good if we could use this on Django's error pages as well.

The new code column information API may be required: ​https://docs.python.org/3.11/whatsnew/3.11.html#column-information-for-code-objects . Note it can be disabled.

[Mariusz Felisiak]

Thanks for the ticket. Let's wait for the final release first.

[Adam Johnson]

Relatedly I also opened #33747 to show exception notes, another feature in Python 3.11

[Giebisch]

I've created a PR (​https://github.com/django/django/pull/16250).
Somehow I am not completely satisfied with the code, so I appreciate feedback.
Still passes all tests and works also with older Python versions.

[Mariusz Felisiak <felisiak.mariusz@…>]

In 85b52d22:

Fixed #33701 -- Added fine-grained error locations to the technical 500 debug page.