gh-83004: Clean up refleak in _io initialisation

[hauntsaninja]

• Issue: Improve stdlib module initialization error handling. #83004

[miss-islington]

Thanks @hauntsaninja for the PR, and @JelleZijlstra for merging it 🌮🎉.. I'm working now to backport this PR to: 3.10.
🐍🍒⛏🤖

[miss-islington]

Thanks @hauntsaninja for the PR, and @JelleZijlstra for merging it 🌮🎉.. I'm working now to backport this PR to: 3.11.
🐍🍒⛏🤖

[miss-islington]

Sorry @hauntsaninja and @JelleZijlstra, I had trouble checking out the 3.10 backport branch.
Please retry by removing and re-adding the "needs backport to 3.10" label.
Alternatively, you can backport using cherry_picker on the command line.
cherry_picker 1208037246eeab4c5c003f1651edfefb045e6fb7 3.10

[bedevere-bot]

GH-99059 is a backport of this pull request to the 3.11 branch.

[miss-islington]

Thanks @hauntsaninja for the PR, and @JelleZijlstra for merging it 🌮🎉.. I'm working now to backport this PR to: 3.10.
🐍🍒⛏🤖

[bedevere-bot]

GH-99060 is a backport of this pull request to the 3.10 branch.

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot PPC64LE RHEL7 LTO 3.10 has failed when building commit 8d44f36.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/all/#builders/640/builds/941) and take a look at the build logs.
4. Check if the failure is related to this commit (8d44f36) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/all/#builders/640/builds/941

Summary of the results of the build (if available):

== Tests result: ENV CHANGED ==

412 tests OK.

10 slowest tests:

• test_gdb: 4 min 18 sec
• test_urllib2net: 2 min 52 sec
• test_multiprocessing_spawn: 2 min 33 sec
• test_concurrent_futures: 2 min 29 sec
• test_multiprocessing_forkserver: 2 min 9 sec
• test_peg_generator: 1 min 52 sec
• test_unparse: 1 min 35 sec
• test_tokenize: 1 min 21 sec
• test_compileall: 1 min 15 sec
• test_venv: 1 min 15 sec

1 test altered the execution environment:
test_multiprocessing_spawn

14 tests skipped:
test_devpoll test_ioctl test_kqueue test_msilib test_smtpnet
test_ssl test_startfile test_tix test_tk test_ttk_guionly
test_winconsoleio test_winreg test_winsound test_zipfile64

Total duration: 5 min 44 sec

Click to see traceback logs

Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.10.cstratak-RHEL7-ppc64le.lto/build/Lib/multiprocessing/resource_tracker.py", line 209, in main
    cache[rtype].remove(name)
KeyError: '/psm_6b1ee4c8'


Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.10.cstratak-RHEL7-ppc64le.lto/build/Lib/multiprocessing/resource_tracker.py", line 209, in main
    cache[rtype].remove(name)
KeyError: '/psm_8448b872'


Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.10.cstratak-RHEL7-ppc64le.lto/build/Lib/multiprocessing/resource_tracker.py", line 209, in main
    cache[rtype].remove(name)
KeyError: '/psm_f70b39f7'
Warning -- Dangling processes: {<SpawnProcess name='SharedMemoryManager-313' pid=16953 parent=6541 started>}
Warning -- Dangling processes: {<SpawnProcess name='SharedMemoryManager-313' pid=16953 parent=6541 stopped exitcode=0>}

[JelleZijlstra]

That doesn't look related to this change.