gh-108308: Replace PyDict_GetItem() with PyDict_GetItemRef()

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Replace PyDict_GetItem() calls with PyDict_GetItemRef() to handle errors.

• Issue: [C API] Use new PyDict_GetItemRef() C API #108308

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cc @serhiy-storchaka

[serhiy-storchaka]

I actually tried to make the compiler code clearer. But it requires so much work that I keep putting it off after another attempt.

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@serhiy-storchaka: I addressed your review. Would you mind to review the updated PR?

[serhiy-storchaka]

LGTM.

[bedevere-bot]

There's a new commit after the PR has been approved.

@serhiy-storchaka: please review the changes made to this pull request.

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Well, writing correct code requires to write more code. IMO it's worth it :-)

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Merged, thanks for the review Serhiy!

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot AMD64 RHEL8 3.x has failed when building commit f5559f3.

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/185/builds/4792) and take a look at the build logs.
4. Check if the failure is related to this commit (f5559f3) 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/185/builds/4792

Failed tests:

• test.test_asyncio.test_unix_events

Failed subtests:

• test_fork_signal_handling - test.test_asyncio.test_unix_events.TestFork.test_fork_signal_handling

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

== Tests result: FAILURE then ENV CHANGED ==

432 tests OK.

10 slowest tests:

• test_gdb: 6 min 2 sec
• test_concurrent_futures: 2 min 32 sec
• test_multiprocessing_spawn: 2 min 27 sec
• test_math: 2 min 3 sec
• test_multiprocessing_forkserver: 1 min 31 sec
• test_multiprocessing_fork: 1 min 18 sec
• test_capi: 58.0 sec
• test_signal: 57.1 sec
• test_unparse: 51.8 sec
• test_tokenize: 51.5 sec

1 test altered the execution environment:
test_ssl

14 tests skipped:
test.test_asyncio.test_windows_events
test.test_asyncio.test_windows_utils test_devpoll test_ioctl
test_kqueue test_launcher test_startfile test_tkinter test_ttk
test_winconsoleio test_winreg test_winsound test_wmi
test_zipfile64

1 re-run test:
test.test_asyncio.test_unix_events

Total duration: 7 min 45 sec

Click to see traceback logs

Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.x.cstratak-RHEL8-x86_64/build/Lib/unittest/async_case.py", line 90, in _callTestMethod
    if self._callMaybeAsync(method) is not None:
       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-RHEL8-x86_64/build/Lib/unittest/async_case.py", line 117, in _callMaybeAsync
    return self._asyncioTestContext.run(func, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-RHEL8-x86_64/build/Lib/test/support/hashlib_helper.py", line 49, in wrapper
    return func_or_class(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-RHEL8-x86_64/build/Lib/test/test_asyncio/test_unix_events.py", line 1937, in test_fork_signal_handling
    self.assertTrue(child_handled.is_set())
AssertionError: False is not true

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot wasm32-emscripten node (pthreads) 3.x has failed when building commit f5559f3.

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/1050/builds/2826) and take a look at the build logs.
4. Check if the failure is related to this commit (f5559f3) 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/1050/builds/2826

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

== Tests result: ENV CHANGED ==

329 tests OK.

10 slowest tests:

• test_math: 2 min 10 sec
• test_hashlib: 1 min 31 sec
• test_unparse: 54.2 sec
• test_tarfile: 43.2 sec
• test_tokenize: 37.2 sec
• test_io: 26.7 sec
• test_unicodedata: 19.5 sec
• test_capi: 19.3 sec
• test_pathlib: 19.1 sec
• test_fstring: 17.7 sec

1 test altered the execution environment:
test_capi

117 tests skipped:
test.test_asyncio.test_base_events
test.test_asyncio.test_buffered_proto
test.test_asyncio.test_context
test.test_asyncio.test_eager_task_factory
test.test_asyncio.test_events test.test_asyncio.test_futures
test.test_asyncio.test_futures2 test.test_asyncio.test_locks
test.test_asyncio.test_pep492
test.test_asyncio.test_proactor_events
test.test_asyncio.test_protocols test.test_asyncio.test_queues
test.test_asyncio.test_runners
test.test_asyncio.test_selector_events
test.test_asyncio.test_sendfile test.test_asyncio.test_server
test.test_asyncio.test_sock_lowlevel test.test_asyncio.test_ssl
test.test_asyncio.test_sslproto test.test_asyncio.test_streams
test.test_asyncio.test_subprocess
test.test_asyncio.test_taskgroups test.test_asyncio.test_tasks
test.test_asyncio.test_threads test.test_asyncio.test_timeouts
test.test_asyncio.test_transports
test.test_asyncio.test_unix_events test.test_asyncio.test_waitfor
test.test_asyncio.test_windows_events
test.test_asyncio.test_windows_utils test__xxinterpchannels
test__xxsubinterpreters test_asyncgen test_clinic test_cmd_line
test_concurrent_futures test_contextlib_async test_ctypes
test_curses test_dbm_gnu test_dbm_ndbm test_devpoll test_doctest
test_docxmlrpc test_dtrace test_embed test_epoll test_faulthandler
test_fcntl test_file_eintr test_fork1 test_ftplib test_gdb
test_generated_cases test_grp test_httplib test_httpservers
test_idle test_imaplib test_interpreters test_ioctl test_kqueue
test_launcher test_lzma test_mmap test_multiprocessing_fork
test_multiprocessing_forkserver test_multiprocessing_main_handling
test_multiprocessing_spawn test_openpty test_pdb
test_perf_profiler test_perfmaps test_poll test_poplib test_pty
test_pwd test_readline test_regrtest test_repl test_resource
test_select test_selectors test_smtplib test_smtpnet test_socket
test_socketserver test_ssl test_stable_abi_ctypes test_startfile
test_subprocess test_sys_settrace test_syslog test_tcl
test_tkinter test_tools test_ttk test_ttk_textonly test_turtle
test_urllib2 test_urllib2_localnet test_urllib2net test_urllibnet
test_venv test_wait3 test_wait4 test_webbrowser test_winconsoleio
test_winreg test_winsound test_wmi test_wsgiref test_xmlrpc
test_xxlimited test_zipfile64 test_zipimport_support test_zoneinfo

Total duration: 21 min 36 sec

Click to see traceback logs

Traceback (most recent call last):
  File "/opt/buildbot/bcannon-wasm/3.x.bcannon-wasm.emscripten-node-pthreads/build/Lib/test/test_capi/test_watchers.py", line 532, in watcher
    raise MyError("testing 123")

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The buildbot wasm32-emscripten node (pthreads) 3.x
1 test altered the execution environment: test_capi

I created #108373 to track this unrelated bug.