Mailman 3 March 2021 - Python-Dev

Merge Request Review Reminder
by Faisal Mahmood 22 Mar '21

22 Mar '21

Hello, I hope you are all well, I currently have an issue / merge request that has become stale and as per the guidelines I am sending this e-mail to request someone to review it for me please. Issue Number: 42861 (https://bugs.python.org/issue42861) Pull Request: 24180 (https://github.com/python/cpython/pull/24180) This is my first contribution to CPython and I am very keen to get this added as I think it is an almost essential enhancement missing from the ipaddress module. I would greatly appreciate if someone can take a look and give me feedback, I am more than happy to help explain things, as I appreciate this is not the most straightforward thing to do. Effectively, this method allows you to get the next closest network of any prefix size, it works by effectively adding 1 to the host portion of the network. There is actually a very nice guide someone made on stackexchange explaining how to do this calculation manually, I simply followed this logic and have tested it as much as possible and it seems to work great. See here: https://networkengineering.stackexchange.com/questions/7106/how-do-you-calc… Please let me know if there is anything else I can do to help get this merged. Kind regards, Faisal.

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Python Language Summit 2021 Signups Are Now Open
by Łukasz Langa 22 Mar '21

22 Mar '21

I’m happy to announce that we’ve opened the sign-up forms for the 2021 Python Language Summit! TL;DR When: Tuesday, May 11, 2021 (4 hours) and Wednesday, May 12, 2021 (4 hours). Exact times TBD depending on attendee timezones. Where: Online via Zoom (link will be sent via email to attendees) Co-chairs: Mariatta Wijaya & Łukasz Langa Blogger: Joanna Jablonski Sign up to attend and actively participate: https://forms.gle/cgmGnmQMDhD2mhHY8 <https://forms.gle/cgmGnmQMDhD2mhHY8> (closes after March 22nd, 2021 AoE) Propose a topic: https://forms.gle/Jui9mxsHrB4fVvAB8 <https://forms.gle/Jui9mxsHrB4fVvAB8> (closes after March 22nd, 2021 AoE) To get an idea of past Python Language Summits, you can read these blog posts: 2020: Python Software Foundation News: The 2020 Python Language Summit <https://pyfound.blogspot.com/2020/04/the-2020-python-language-summit.html> 2019: http://pyfound.blogspot.com/2019/05/the-2019-python-language-summit.html <http://pyfound.blogspot.com/2019/05/the-2019-python-language-summit.html> 2018: The 2018 Python Language Summit [LWN.net] <https://lwn.net/Articles/754152/> 2017: The 2017 Python Language Summit [LWN.net] <https://lwn.net/Articles/723251/> Do I need to sign up if I’m a Python core developer? Yes please! While in the past we have limited attendance to 50 people, this time, due to virtual format, we will be a bit more flexible, but will still keep it small and manageable. We aren’t planning to go beyond 80 participants. Please register to reserve your space. Can I sign up if I’m not a Python core developer? Yes you can. In the past, we had quite a number of participants who were not Python core devs. Among them were maintainers and representatives from BeeWare, CircuitPython, PSF board member, PyCharm, PyPA, etc. Register if you want to participate. Note that until you hear back from us, your attendance is not confirmed. As explained in the question above, our “space” is more flexible than usual, but in the interest of maintaining a vigorous discussion space, we might still be unable to invite everyone who signs up. What kind of topics are covered? Python Language Summit is a special event with very specific audience: Python core developers. Ideally your topic is not an “announcement” or “project status” but rather something that will encourage further discussion and questions. The more controversial, the better. An open issue, group of issues, or a PEP that is awaiting decision are all good topics to propose. You can also further explain why this is better discussed in person instead of online. According to last year’s feedback, our audience prefer more discussions and shorter talks. Who can present a talk? Anyone, even if you’re not a Python core developer. However, please understand that we will have to be selective as space and time are limited. In particular, we are prioritizing active core contributors, as well as those who we believe will be able to improve the quality of the discussions at the event and bring a more diverse perspective to core Python developers. Note that your topic is not confirmed until you hear back from us. Code of Conduct PyCon’s Code of Conduct <https://us.pycon.org/2020/about/code-of-conduct/> applies and will be enforced. Thanks! @mariatta <https://discuss.python.org/u/mariatta> & @ambv <https://discuss.python.org/u/ambv>

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Fwd: Re: aiter/anext review request
by Joshua Bronson 22 Mar '21

22 Mar '21

On Sat, Mar 20, 2021 at 8:03 PM Guido van Rossum <guido(a)python.org> wrote: > The operator module is also C. > (In my 2018 PR, I was able to add the Python implementations of `aiter` and `anext` to Lib/operator.py, right above where it does "from _operator import *" toward the bottom of the file. I interpreted this pattern there to mean "shadow Python implementations with C implementations where available, but otherwise it's okay to use the Python implementations above". Is that right?) Dan also suggested freezing the Python implementations into the binary as a way of keeping their implementations in Python, but in builtins rather than operator. > I am pleading to remove the 2nd arg to aiter, which should simplify the > code. > Done in the latest revision of https://github.com/python/cpython/pull/23847. That does indeed simplify the patch significantly, nice.[1] All checks are passing. Yury or any other core developers, would you like to merge this now? Thanks again, everyone. --Josh, Dan, and Justin [1] The latest revision adds the following to the `aiter` docs: Unlike the :func:`iter` builtin, :func:`aiter` has no 2-argument variant. Often, this variant can be replaced with assignment expressions:: while chunk := await sock.read(CHUNK_SIZE): ... I think when I originally worked on this in 2018, PEP 572 had only just been approved. :-)

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Buildbot UI auto-refreshes
by Antoine Pitrou 21 Mar '21

21 Mar '21

Hello, It seems the buildbot Web UI has the bad habit of auto-refreshing itself (by doing a full page reload) every minute or two. I also couldn't find a setting to disable it (despite being logged in). Am I missing something? Regards Antoine.

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aiter/anext review request
by Joshua Bronson 20 Mar '21

20 Mar '21

Dear python-dev, New here (but not to Python). 👋 Brett Cannon recommended I start a thread here (thanks, Brett!). In December, two colleagues and I submitted https://github.com/python/cpython/pull/23847, "Add aiter and anext to builtins", which would fix https://bugs.python.org/issue31861. Would any core developers who may be reading this be willing and able to provide a code review? We would love to try to address any review feedback before having to fix (another round of) merge conflicts. (And ideally maybe even get this landed in time for the 3.10 feature freeze in early May?) Thanks and hope this finds you well.

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Re: aiter/anext review request
by Daniel Pope 20 Mar '21

20 Mar '21

As someone who was involved in implementing these, I think they should not be in builtins if that means they have to be in C. My argument is from a point of maintainability. Writing them was plenty of effort in the first place; Josh had written them in idiomatic async Python in the first place, my contribution was to unroll that to sync Python code, and then port that to (sync) C code. It was a lot of effort and a lot of code - several hundred lines and 4(?) new types. The Python code was a few lines - very readable and likely to be practically as fast. We weren't writing this in C to speed it up or to make the code better, but because we *had to*. Implementing async functionality in C is a pain because to implement an awaitable type you need not just that awaitable type, but a new type to represent the iterator that am_await returns. I could imagine having generic type objects and other helpers for implementing async PyObjects in C but I don't really envisage anyone doing that; if you want to write async helpers for Python the best framework is Python. As Josh can attest I was in two minds while implementing this change; I argued firstly that having them in the operator module is fine, and later, that if we want async builtins in general, maybe we could implement them in Python and freeze them into the binary. We pushed on with the C approach mostly because we were already 70% done, and this was what Yury asked for, so it seemed more likely that this would get merged. But, if we're still discussing whether this should be merged in builtins or operator, and that dictates whether it is in Python or C, I'm 100% behind having this code be Python.

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pth file encoding
by Inada Naoki 19 Mar '21

19 Mar '21

Hi, all. I found .pth file is decoded by the default (i.e. locale-specific) encoding. https://github.com/python/cpython/blob/0269ce87c9347542c54a653dd78b9f60bb9f… pth files contain: * import statements * paths For import statement, UTF-8 is the default Python code encoding. For paths, fsencoding is the right encoding. It is UTF-8 on Windows (excpet PYTHONLEGACYWINDOWSFSENCODING is set), and locale-specific encoding in Linux. What encoding should we use? * UTF-8 * sys.getfilesystemencoding() * Keep status-quo. Regards, -- Inada Naoki <songofacandy(a)gmail.com>

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Summary of Python tracker Issues
by Python tracker 19 Mar '21

19 Mar '21

ACTIVITY SUMMARY (2021-03-12 - 2021-03-19) Python tracker at https://bugs.python.org/ To view or respond to any of the issues listed below, click on the issue. Do NOT respond to this message. Issues counts and deltas: open 7481 ( +3) closed 47813 (+75) total 55294 (+78) Open issues with patches: 2980 Issues opened (66) ================== #35943: PyImport_GetModule() can return partially-initialized module https://bugs.python.org/issue35943 reopened by pitrou #37788: fix for bpo-36402 (threading._shutdown() race condition) cause https://bugs.python.org/issue37788 reopened by mark.dickinson #42161: Remove private _PyLong_Zero and _PyLong_One variables https://bugs.python.org/issue42161 reopened by rhettinger #43334: venv does not install libpython https://bugs.python.org/issue43334 reopened by anuppari #43439: [security] Add audit events on GC functions giving access to a https://bugs.python.org/issue43439 reopened by steve.dower #43481: PyEval_EvalCode() namespace issue not observed in Python 2.7. https://bugs.python.org/issue43481 opened by chrisgmorton #43482: Py_AddPendingCall Inserted Function Never Called in 3.8, works https://bugs.python.org/issue43482 opened by chrisgmorton #43484: we can create valid datetime objects that become invalid if th https://bugs.python.org/issue43484 opened by zzzeek #43486: Python 3.9 installer not updating ARP table https://bugs.python.org/issue43486 opened by codaamok #43487: Rename __unicode__ methods to __str__ in 2to3 conversion https://bugs.python.org/issue43487 opened by bartbroere #43490: IDLE freezes at random https://bugs.python.org/issue43490 opened by aledeaux #43492: Upgrade to SQLite 3.35.2 in macOS and Windows https://bugs.python.org/issue43492 opened by erlendaasland #43493: EmailMessage mis-folding headers of a certain length https://bugs.python.org/issue43493 opened by mglover #43494: Minor changes to Objects/lnotab_notes.txt https://bugs.python.org/issue43494 opened by skip.montanaro #43495: Missing frame block push in compiler_async_comprehension_gener https://bugs.python.org/issue43495 opened by tomkpz #43497: SyntaxWarning for "assertion is always true, perhaps remove pa https://bugs.python.org/issue43497 opened by darke #43498: "dictionary changed size during iteration" error in _ExecutorM https://bugs.python.org/issue43498 opened by kulikjak #43500: Add filtercase() into fnmatch https://bugs.python.org/issue43500 opened by wyz23x2 #43501: email._header_value_parse throws AttributeError on display nam https://bugs.python.org/issue43501 opened by elenril #43502: [C-API] Convert obvious unsafe macros to static inline functio https://bugs.python.org/issue43502 opened by erlendaasland #43503: [subinterpreters] PyObject statics exposed in the limited API https://bugs.python.org/issue43503 opened by eric.snow #43504: effbot.org down https://bugs.python.org/issue43504 opened by mdk #43505: [sqlite3] Explicitly initialise and shut down sqlite3 https://bugs.python.org/issue43505 opened by erlendaasland #43508: Miscompilation information for tarfile.open() when given too m https://bugs.python.org/issue43508 opened by xxm #43509: CFunctionType object should be hashable in Python https://bugs.python.org/issue43509 opened by xxm #43510: PEP 597: Implemente encoding="locale" option and EncodingWarni https://bugs.python.org/issue43510 opened by methane #43511: tkinter with Tk 8.6.11 is slow on macOS https://bugs.python.org/issue43511 opened by thomaswamm #43513: venv: recreate symlinks on --upgrade https://bugs.python.org/issue43513 opened by ThiefMaster #43514: Disallow fork in a subinterpreter affects multiprocessing plug https://bugs.python.org/issue43514 opened by franku #43517: Fix false positives in circular import detection with from-imp https://bugs.python.org/issue43517 opened by pitrou #43518: textwrap.shorten does not always respect word boundaries https://bugs.python.org/issue43518 opened by annesylvie #43520: Fraction only handles regular slashes ("/") and fails with oth https://bugs.python.org/issue43520 opened by weightwatchers-carlanderson #43522: SSLContext.hostname_checks_common_name appears to have no effe https://bugs.python.org/issue43522 opened by Quentin.Pradet #43523: Handling Ctrl+C while waiting on I/O in Windows https://bugs.python.org/issue43523 opened by sovetov #43524: Addition of peek and peekexactly methods to asyncio.StreamRead https://bugs.python.org/issue43524 opened by awalgarg #43525: pathlib: Highlight pathlib operator behavior with anchored pat https://bugs.python.org/issue43525 opened by diegoe #43526: Programmatic management of BytesWarning doesn't work for nativ https://bugs.python.org/issue43526 opened by xmorel #43527: Support full stack trace extraction in warnings. https://bugs.python.org/issue43527 opened by xmorel #43528: "connect_read_pipe" raises errors on Windows for STDIN https://bugs.python.org/issue43528 opened by ivankravets #43529: pathlib.Path.glob causes OSError encountering symlinks to long https://bugs.python.org/issue43529 opened by eric.frederich #43530: email.parser.BytesParser failed to parse mail when it is with https://bugs.python.org/issue43530 opened by tzing #43532: Add keyword-only fields to dataclasses https://bugs.python.org/issue43532 opened by eric.smith #43533: Exception and contextmanager in __getattr__ causes reference c https://bugs.python.org/issue43533 opened by crccw #43534: turtle.textinput window is not transient https://bugs.python.org/issue43534 opened by quid256 #43535: Make str.join auto-convert inputs to strings. https://bugs.python.org/issue43535 opened by rhettinger #43536: 3.9.2 --without-pymalloc --with-pydebug --with-valgrind: test https://bugs.python.org/issue43536 opened by Thermi #43537: interpreter crashes when handling long text in input() https://bugs.python.org/issue43537 opened by xxm #43538: [Windows] support args and cwd in os.startfile() https://bugs.python.org/issue43538 opened by eryksun #43539: test_asyncio: test_sendfile_close_peer_in_the_middle_of_receiv https://bugs.python.org/issue43539 opened by vstinner #43540: importlib: Document how to replace load_module() in What's New https://bugs.python.org/issue43540 opened by vstinner #43542: Add image/heif(heic) to list of media types in mimetypes.py https://bugs.python.org/issue43542 opened by martbln #43544: mimetype default list make a wrong guess for illustrator file https://bugs.python.org/issue43544 opened by Inkhey #43545: Use LOAD_GLOBAL to set __module__ in class def https://bugs.python.org/issue43545 opened by bup #43546: "Impossible" KeyError from importlib._bootstrap acquire line 1 https://bugs.python.org/issue43546 opened by anentropic #43547: support ZIP files with zeroed out fields (e.g. for reproducibl https://bugs.python.org/issue43547 opened by eighthave #43548: RecursionError depth exceptions break pdb's interactive tracin https://bugs.python.org/issue43548 opened by behindthebrain #43549: Outdated descriptions for configuring valgrind. https://bugs.python.org/issue43549 opened by xxm #43550: pip.exe is missing from the NuGet package https://bugs.python.org/issue43550 opened by gipetrou #43551: [Subinterpreters]: PyImport_Import use static silly_list under https://bugs.python.org/issue43551 opened by JunyiXie #43552: Add locale.get_locale_encoding() and locale.get_current_locale https://bugs.python.org/issue43552 opened by vstinner #43553: [sqlite3] Improve test coverage https://bugs.python.org/issue43553 opened by erlendaasland #43554: email: encoded headers lose their quoting when refolded https://bugs.python.org/issue43554 opened by Emil.Styrke #43555: Location of SyntaxError with new parser missing (after continu https://bugs.python.org/issue43555 opened by aroberge #43556: fix attr names for ast.expr and ast.stmt https://bugs.python.org/issue43556 opened by samwyse #43557: Deprecate getdefaultlocale(), getlocale() and normalize() func https://bugs.python.org/issue43557 opened by vstinner #43558: The dataclasses documentation should mention how to call super https://bugs.python.org/issue43558 opened by eric.smith Most recent 15 issues with no replies (15) ========================================== #43558: The dataclasses documentation should mention how to call super https://bugs.python.org/issue43558 #43556: fix attr names for ast.expr and ast.stmt https://bugs.python.org/issue43556 #43555: Location of SyntaxError with new parser missing (after continu https://bugs.python.org/issue43555 #43554: email: encoded headers lose their quoting when refolded https://bugs.python.org/issue43554 #43553: [sqlite3] Improve test coverage https://bugs.python.org/issue43553 #43551: [Subinterpreters]: PyImport_Import use static silly_list under https://bugs.python.org/issue43551 #43550: pip.exe is missing from the NuGet package https://bugs.python.org/issue43550 #43549: Outdated descriptions for configuring valgrind. https://bugs.python.org/issue43549 #43548: RecursionError depth exceptions break pdb's interactive tracin https://bugs.python.org/issue43548 #43545: Use LOAD_GLOBAL to set __module__ in class def https://bugs.python.org/issue43545 #43544: mimetype default list make a wrong guess for illustrator file https://bugs.python.org/issue43544 #43542: Add image/heif(heic) to list of media types in mimetypes.py https://bugs.python.org/issue43542 #43538: [Windows] support args and cwd in os.startfile() https://bugs.python.org/issue43538 #43533: Exception and contextmanager in __getattr__ causes reference c https://bugs.python.org/issue43533 #43530: email.parser.BytesParser failed to parse mail when it is with https://bugs.python.org/issue43530 Most recent 15 issues waiting for review (15) ============================================= #43553: [sqlite3] Improve test coverage https://bugs.python.org/issue43553 #43552: Add locale.get_locale_encoding() and locale.get_current_locale https://bugs.python.org/issue43552 #43551: [Subinterpreters]: PyImport_Import use static silly_list under https://bugs.python.org/issue43551 #43542: Add image/heif(heic) to list of media types in mimetypes.py https://bugs.python.org/issue43542 #43534: turtle.textinput window is not transient https://bugs.python.org/issue43534 #43532: Add keyword-only fields to dataclasses https://bugs.python.org/issue43532 #43525: pathlib: Highlight pathlib operator behavior with anchored pat https://bugs.python.org/issue43525 #43522: SSLContext.hostname_checks_common_name appears to have no effe https://bugs.python.org/issue43522 #43517: Fix false positives in circular import detection with from-imp https://bugs.python.org/issue43517 #43510: PEP 597: Implemente encoding="locale" option and EncodingWarni https://bugs.python.org/issue43510 #43503: [subinterpreters] PyObject statics exposed in the limited API https://bugs.python.org/issue43503 #43502: [C-API] Convert obvious unsafe macros to static inline functio https://bugs.python.org/issue43502 #43501: email._header_value_parse throws AttributeError on display nam https://bugs.python.org/issue43501 #43498: "dictionary changed size during iteration" error in _ExecutorM https://bugs.python.org/issue43498 #43497: SyntaxWarning for "assertion is always true, perhaps remove pa https://bugs.python.org/issue43497 Top 10 most discussed issues (10) ================================= #43552: Add locale.get_locale_encoding() and locale.get_current_locale https://bugs.python.org/issue43552 25 msgs #42128: Structural Pattern Matching (PEP 634) https://bugs.python.org/issue42128 13 msgs #43503: [subinterpreters] PyObject statics exposed in the limited API https://bugs.python.org/issue43503 13 msgs #43313: feature: support pymalloc for subinterpreters. each subinterpr https://bugs.python.org/issue43313 9 msgs #43502: [C-API] Convert obvious unsafe macros to static inline functio https://bugs.python.org/issue43502 9 msgs #43475: Worst-case behaviour of hash collision with float NaN https://bugs.python.org/issue43475 8 msgs #43244: Move PyArena C API to the internal C API https://bugs.python.org/issue43244 7 msgs #43466: ssl/hashlib: Add configure option to set or auto-detect rpath https://bugs.python.org/issue43466 7 msgs #43478: Disallow Mock spec arguments from being Mocks https://bugs.python.org/issue43478 7 msgs #35883: Python startup fails with a fatal error if a command line argu https://bugs.python.org/issue35883 6 msgs Issues closed (74) ================== #12777: Inconsistent use of VOLUME_NAME_* with GetFinalPathNameByHandl https://bugs.python.org/issue12777 closed by eryksun #15453: ctype with packed bitfields does not match native compiler https://bugs.python.org/issue15453 closed by eryksun #15698: PEP 3121, 384 Refactoring applied to pyexpat module https://bugs.python.org/issue15698 closed by vstinner #18017: ctypes.PyDLL documentation https://bugs.python.org/issue18017 closed by eryksun #22781: ctypes: Differing results between Python and C. https://bugs.python.org/issue22781 closed by eryksun #25012: pathlib should allow converting to absolute paths without reso https://bugs.python.org/issue25012 closed by eryksun #25117: Windows installer: precompiling stdlib fails with missing DLL https://bugs.python.org/issue25117 closed by steve.dower #26882: The Python process stops responding immediately after starting https://bugs.python.org/issue26882 closed by eryksun #27820: Possible bug in smtplib when initial_response_ok=False https://bugs.python.org/issue27820 closed by orsenthil #28344: Python 3.5.2 installer hangs when run in session 0 https://bugs.python.org/issue28344 closed by eryksun #29586: Cannot run pip in fresh install of py 3.5.3 https://bugs.python.org/issue29586 closed by steve.dower #29687: smtplib does not support proxy https://bugs.python.org/issue29687 closed by christian.heimes #29982: tempfile.TemporaryDirectory fails to delete itself https://bugs.python.org/issue29982 closed by gvanrossum #31103: Windows Installer Product does not include micro version in di https://bugs.python.org/issue31103 closed by steve.dower #32434: pathlib.WindowsPath.reslove(strict=False) returns absoulte pat https://bugs.python.org/issue32434 closed by eryksun #33129: Add kwarg-only option to dataclass https://bugs.python.org/issue33129 closed by eric.smith #33136: Harden ssl module against CVE-2018-8970 https://bugs.python.org/issue33136 closed by gregory.p.smith #33159: Implement PEP 473 https://bugs.python.org/issue33159 closed by skreft #33603: Subprocess Thread handles grow with each call and aren't relea https://bugs.python.org/issue33603 closed by eryksun #33780: [subprocess] Better Unicode support for shell=True on Windows https://bugs.python.org/issue33780 closed by eryksun #34187: Issues with lazy fd support in _WindowsConsoleIO fileno() and https://bugs.python.org/issue34187 closed by eryksun #34840: dlopen() error with no error message from dlerror() https://bugs.python.org/issue34840 closed by eryksun #35216: misleading error message from shutil.copy() https://bugs.python.org/issue35216 closed by eryksun #36646: os.listdir() got permission error in Python3.6 but it's fine i https://bugs.python.org/issue36646 closed by eryksun #37820: Unnecessary URL scheme exists to allow 'URL: reading file in u https://bugs.python.org/issue37820 closed by christian.heimes #39340: shutil.rmtree and write protected files https://bugs.python.org/issue39340 closed by eryksun #39342: Expose X509_V_FLAG_ALLOW_PROXY_CERTS in ssl https://bugs.python.org/issue39342 closed by christian.heimes #40540: inconstent stdin buffering/seeking behaviour https://bugs.python.org/issue40540 closed by eryksun #40763: zipfile.extractall is safe by now https://bugs.python.org/issue40763 closed by gregory.p.smith #41123: Remove Py_UNICODE APIs except PEP 623 https://bugs.python.org/issue41123 closed by methane #41200: Add pickle.loads fuzz test https://bugs.python.org/issue41200 closed by gregory.p.smith #41567: multiprocessing.Pool from concurrent threads failure on 3.9.0r https://bugs.python.org/issue41567 closed by pitrou #41883: ctypes pointee goes out of scope, then pointer in struct dangl https://bugs.python.org/issue41883 closed by eryksun #41933: Wording of s * n in Common Sequence Operations is not optimal https://bugs.python.org/issue41933 closed by mdk #42322: Spectre mitigations in CPython interpreter https://bugs.python.org/issue42322 closed by gregory.p.smith #42370: test_ttk_guionly: test_to() fails on the GitHub Ubuntu job https://bugs.python.org/issue42370 closed by vstinner #42730: TypeError/hang inside of Time.Sleep() when _thread.interrupt_m https://bugs.python.org/issue42730 closed by eryksun #43065: Delegating to thread and process deadlocks https://bugs.python.org/issue43065 closed by doublex #43068: test_subprocess: test_specific_shell() fails on AMD64 FreeBSD https://bugs.python.org/issue43068 closed by vstinner #43175: filecmp is not working for UTF-8 BOM file. https://bugs.python.org/issue43175 closed by eryksun #43199: FAQ about goto lacks answer https://bugs.python.org/issue43199 closed by terry.reedy #43214: site: Potential UnicodeDecodeError when handling pth file https://bugs.python.org/issue43214 closed by methane #43228: Regression in function builtins https://bugs.python.org/issue43228 closed by vstinner #43245: Add keyword argument support to ChainMap.new_child() https://bugs.python.org/issue43245 closed by rhettinger #43285: ftplib should not use the host from the PASV response https://bugs.python.org/issue43285 closed by gregory.p.smith #43353: Document that logging.getLevelName() can return a numeric valu https://bugs.python.org/issue43353 closed by felixxm #43357: Python memory cleaning https://bugs.python.org/issue43357 closed by gregory.p.smith #43382: github CI blocked by the Ubuntu CI with an SSL error https://bugs.python.org/issue43382 closed by christian.heimes #43410: Parser does not handle correctly some errors when parsin from https://bugs.python.org/issue43410 closed by pablogsal #43427: Possible error on the descriptor howto guide https://bugs.python.org/issue43427 closed by rhettinger #43428: Sync importlib_metadata enhancements through 3.7. https://bugs.python.org/issue43428 closed by jaraco #43437: venv activate bash script has wrong line endings on windows https://bugs.python.org/issue43437 closed by eryksun #43441: [Subinterpreters]: global variable next_version_tag cause meth https://bugs.python.org/issue43441 closed by vstinner #43444: [sqlite3] Move MODULE_NAME def from setup.py to module.h https://bugs.python.org/issue43444 closed by berker.peksag #43462: canvas.bbox returns None on 'hidden' items while coords doesn' https://bugs.python.org/issue43462 closed by Vincent #43477: from x import * behavior inconsistent between module types. https://bugs.python.org/issue43477 closed by brett.cannon #43479: Remove a duplicate comment and assignment in http.client https://bugs.python.org/issue43479 closed by orsenthil #43483: Loss of content in simple (but oversize) SAX parsing https://bugs.python.org/issue43483 closed by ridgerat1611 #43485: Spam https://bugs.python.org/issue43485 closed by zach.ware #43488: Added new methods to vector.py https://bugs.python.org/issue43488 closed by rhettinger #43489: Can't install, nothing to install https://bugs.python.org/issue43489 closed by ned.deily #43491: Windows filepath bug https://bugs.python.org/issue43491 closed by eryksun #43496: macOS tkinter Save As doesn't accept keyboard shortcuts https://bugs.python.org/issue43496 closed by terry.reedy #43499: Compiler warnings in building Python 3.9 on Windows https://bugs.python.org/issue43499 closed by serhiy.storchaka #43506: PEP 624: Update document for removal schedule https://bugs.python.org/issue43506 closed by methane #43507: Variables in locals scope fails to be printed. https://bugs.python.org/issue43507 closed by mark.dickinson #43512: Bug in isinstance(instance, cls) with cls being a protocol? (P https://bugs.python.org/issue43512 closed by gvanrossum #43515: Lazy import in concurrent.futures produces partial import erro https://bugs.python.org/issue43515 closed by pitrou #43516: python on raspberry pi https://bugs.python.org/issue43516 closed by eric.smith #43519: access python private variable https://bugs.python.org/issue43519 closed by steven.daprano #43521: Allow `ast.unparse` to handle NaNs and empty sets https://bugs.python.org/issue43521 closed by pablogsal #43531: Turtle module does not work https://bugs.python.org/issue43531 closed by mark.dickinson #43541: PyEval_EvalCodeEx() can no longer be called with code which ha https://bugs.python.org/issue43541 closed by vstinner #43543: Spam https://bugs.python.org/issue43543 closed by petr.viktorin

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PEP 654 -- Exception Groups and except* : request for feedback for SC submission
by Irit Katriel 18 Mar '21

18 Mar '21

Hi all, We would like to request feedback on PEP 654 -- Exception Groups and except*. https://www.python.org/dev/peps/pep-0654/ It proposes language extensions that allow programs to raise and handle multiple unrelated exceptions simultaneously, motivated by the needs of asyncio and other concurrency libraries, but with other use cases as well. * A new standard exception type, ExceptionGroup, to represent multiple exceptions with shared traceback. * Updates to the traceback printing code to display (possibly nested) ExceptionGroups. * A new syntax except* for handling ExceptionGroups. A reference implementation (unreviewed) can be found at: https://github.com/iritkatriel/cpython/pull/10 Thank you for your help Kind regards Irit, Yury & Guido

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Non-monotonically increasing line numbers in dis.findlinestarts() output
by Skip Montanaro 18 Mar '21

18 Mar '21

Consider this little session from the tip of the spear: >>> sys.version '3.10.0a6+ (heads/master:0ab152c6b5, Mar 15 2021, 17:24:38) [GCC 10.2.0]' >>> def while2(a): ... while a >= 0: ... a -= 1 ... return a ... >>> dis.dis(while2) 2 0 LOAD_FAST 0 (a) 2 LOAD_CONST 1 (0) 4 COMPARE_OP 5 (>=) 6 POP_JUMP_IF_FALSE 24 3 >> 8 LOAD_FAST 0 (a) 10 LOAD_CONST 2 (1) 12 INPLACE_SUBTRACT 14 STORE_FAST 0 (a) 2 16 LOAD_FAST 0 (a) 18 LOAD_CONST 1 (0) 20 COMPARE_OP 5 (>=) 22 POP_JUMP_IF_TRUE 8 4 >> 24 LOAD_FAST 0 (a) 26 RETURN_VALUE >>> list(dis.findlinestarts(while2.__code__)) [(0, 2), (8, 3), (16, 2), (24, 4)] I get that somewhere along the way the compiler has been optimized to duplicate the loop's test so as to eliminate some jumps (perhaps). It's not clear to me that the line number should be "2" in the duplicated test though. Shouldn't it be "3"? I stumbled on this while trying to generate a line number table in my side project register VM. As I understand it, the line number delta in the output table is supposed to always be >= 0. In my code I'm using dis.findlinestarts() to determine the line numbers for each block. Perhaps I should be modifying its results. OTOH, maybe it's a bug. (If that's the consensus, I will create an issue.) Skip

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