smtpd uses asynchat which has been deprecated since 3.6.

See discussion at
https://mail.python.org/archives/list/python-committers@python.org/thread/KNF6YQE2O4OLJDNKSGAT4NLZUNCQ5QSH/#KNF6YQE2O4OLJDNKSGAT4NLZUNCQ5QSH

There are some tests that use asynchat, asyncore and smtpd so we first move them to test.support and document their removal from the stdlib.

+1 for removal

Please follow the backwards compatibility policy (PEP 387):
- Have a discussion
- Raise deprecation warnings
- Wait at least two minor Python versions where warnings are raised
- Consider any feedback
- Then remove stuff
(Or ask the SC for an exception, but these "are only granted for extreme situations such as dangerously broken or insecure features or features no one could reasonably be depending on".)

There were no deprecation warnings raised so far, so removing these in 3.11 is very premature.

I'm with Petr, please follow PEP 4 and PEP 387. At a bare minimum you should have one minor Python version with deprecation warnings. You could ask Pablo if he allows to add deprecation warnings to Python 3.10 beta.

I'm fine with a 3.10 backport as long as this is mentioned in python-dev to give time for folks to raise concerns. Additionally, please make sure that:

*The test site runs with -Werror as these warnings may make it fail so tests may need to be adapted.
* This deprecation is covered in the 3.10 what's new document.
* There is enough time for people to raise objections to the inclusion in 3.10 (so don't merge immediately after mentioning in python-dwv ;) )

Pablo, to be clear - my understanding is that the question to python-dev is not whether to deprecate or not (they have been deprecated for a long time), but only whether to issue the warning in 3.10 or 3.11. Is that correct?

> but only whether to issue the warning in 3.10 or 3.11. Is that correct?

Correct. It can also be mentioned in a more general message as long as people know that this is the plan and they have a chance to voice any concern to start on 3.10

New changeset 8488b85c6397fe58f17fc00e047044c959ac0b04 by Barry Warsaw in branch 'main':
bpo-44498: Issue a deprecation warning on asynchat, asyncore and smtpd import (#26882)
https://github.com/python/cpython/commit/8488b85c6397fe58f17fc00e047044c959ac0b04

New changeset a80a38ee9a7b2e26dba848793cc298d8435fddd5 by Miss Islington (bot) in branch '3.10':
[3.10] bpo-44498: Issue a deprecation warning on asynchat, asyncore and smtpd import (GH-26882) (GH-26904)
https://github.com/python/cpython/commit/a80a38ee9a7b2e26dba848793cc298d8435fddd5

New changeset 22e7effad571f8e524d2f71ff55bbf2a25306753 by Irit Katriel in branch 'main':
bpo-44498: suppress DeprecationWarnings for asynchat, asyncore and smtpd in tests (GH-26905)
https://github.com/python/cpython/commit/22e7effad571f8e524d2f71ff55bbf2a25306753

New changeset 8bec9fb92f09d02c24611ebd0a90103a1a414a40 by Miss Islington (bot) in branch '3.10':
bpo-44498: suppress DeprecationWarnings for asynchat, asyncore and smtpd in tests (GH-26905) (GH-26907)
https://github.com/python/cpython/commit/8bec9fb92f09d02c24611ebd0a90103a1a414a40