Mailman 3 May 2021 - Python-Dev

PEP 659: Specializing Adaptive Interpreter
by Mark Shannon May 29, 2021

May 29, 2021

Hi everyone, I would like to present PEP 659. This is an informational PEP about a key part of our plan to improve CPython performance for 3.11 and beyond. For those of you aware of the recent releases of Cinder and Pyston, PEP 659 might look similar. It is similar, but I believe PEP 659 offers better interpreter performance and is more suitable to a collaborative, open-source development model. As always, comments and suggestions are welcome. Cheers, Mark. Links: https://www.python.org/dev/peps/pep-0659/ https://github.com/facebookincubator/cinder https://github.com/pyston/pyston

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Summary of Python tracker Issues
by Python tracker May 28, 2021

May 28, 2021

ACTIVITY SUMMARY (2021-05-21 - 2021-05-28) 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 7424 (-28) closed 48574 (+82) total 55998 (+54) Open issues with patches: 2945 Issues opened (38) ================== #44209: urllib.robotparser fail on Disallow: /? from google.com https://bugs.python.org/issue44209 opened by karl.pradene #44210: Make importlib.metadata._meta.PackageMetadata public https://bugs.python.org/issue44210 opened by FFY00 #44211: Duplicate '.bmp' key in mimetypes.py, maps to both 'image/bmp' https://bugs.python.org/issue44211 opened by andreasjansson #44212: asyncio overrides signal handlers https://bugs.python.org/issue44212 opened by Francisco Demartino #44213: LIST_TO_TUPLE placed below the sentence "all of the following https://bugs.python.org/issue44213 opened by glubs9 #44214: PyArg_Parse* for vectorcall? https://bugs.python.org/issue44214 opened by ronaldoussoren #44215: help() module listing displays import warnings from deprecated https://bugs.python.org/issue44215 opened by stefanor #44217: Tkinter/IDLE: literal astral char discombobulates text editing https://bugs.python.org/issue44217 opened by shreyanavigyan #44218: Possible Stack Based Buffer Overflow at Programs/_freeze_impor https://bugs.python.org/issue44218 opened by demonia #44219: Opening a file holds the GIL when it calls "isatty()" https://bugs.python.org/issue44219 opened by smurfix #44220: PyStructSequence_UnnamedField unavailable on Windows https://bugs.python.org/issue44220 opened by johnboy2 #44221: ImportError: sys.meta_path is None, Python is likely shutting https://bugs.python.org/issue44221 opened by luizoti #44225: stop() on a stopped loop inhibits the next run_forever https://bugs.python.org/issue44225 opened by mandolaerik #44226: Threads shutting down in Py 2.7 but not in Py 3.69 while makin https://bugs.python.org/issue44226 opened by muralidhar.bn #44229: Intermittent connection errors in ssl tests on macOS CI https://bugs.python.org/issue44229 opened by erlendaasland #44230: lookup extensions with the stable ABI under a platform specifi https://bugs.python.org/issue44230 opened by doko #44233: Provide Windows Terminal Fragment Extension https://bugs.python.org/issue44233 opened by mveril #44234: Debugging with LLDB doesn't work for universal2 installer on m https://bugs.python.org/issue44234 opened by ronaldoussoren #44235: Remove l*gettext() and related functions in the gettext module https://bugs.python.org/issue44235 opened by corona10 #44236: Define SOABI, LIBRARY, LDLIBRARY and LIBPL on Windows https://bugs.python.org/issue44236 opened by steve.dower #44237: test_ssl randomly fails on macOS GH Action: test_get_server_ce https://bugs.python.org/issue44237 opened by vstinner #44238: Unable to install Python 3.9.5 - Windows Server https://bugs.python.org/issue44238 opened by RFuentes #44239: Use platform defined data directories instead of ~/.python_his https://bugs.python.org/issue44239 opened by oxalica #44240: Incorrect behavior of LOAD_ATTR due to overflow in tp_version https://bugs.python.org/issue44240 opened by Mark.Shannon #44242: enum.IntFlag regression: missing values cause TypeError https://bugs.python.org/issue44242 opened by hroncok #44245: Cross-compilation of CPython 3.8 with _socket module using And https://bugs.python.org/issue44245 opened by laheller #44246: 3.10 beta 1: breaking change in importlib.metadata entry point https://bugs.python.org/issue44246 opened by Anthony Sottile #44249: Readme typo fix https://bugs.python.org/issue44249 opened by Ayushparikh-code #44251: ctypes '_get_soname' fails silently on missing objdump https://bugs.python.org/issue44251 opened by GuillaumeDesforges #44252: test_ssl and test_httplib.HTTPSTest crash randomly with "Windo https://bugs.python.org/issue44252 opened by vstinner #44254: Change turtledemo button colors https://bugs.python.org/issue44254 opened by terry.reedy #44255: strptime and week numbers without week days https://bugs.python.org/issue44255 opened by Jaap van der Velde #44257: typo and verbous grammar in the grammar spec https://bugs.python.org/issue44257 opened by orangebana15 #44258: Support PEP 515 for Fraction's initialization from string https://bugs.python.org/issue44258 opened by Sergey.Kirpichev #44259: lib2to3 does not accept "exec" as name https://bugs.python.org/issue44259 opened by mulugruntz #44260: _Random.seed() is called twice https://bugs.python.org/issue44260 opened by serhiy.storchaka #44261: SocketType documentation misleading https://bugs.python.org/issue44261 opened by srittau #44262: tarfile: some content different output https://bugs.python.org/issue44262 opened by yellowhat Most recent 15 issues with no replies (15) ========================================== #44262: tarfile: some content different output https://bugs.python.org/issue44262 #44261: SocketType documentation misleading https://bugs.python.org/issue44261 #44260: _Random.seed() is called twice https://bugs.python.org/issue44260 #44259: lib2to3 does not accept "exec" as name https://bugs.python.org/issue44259 #44257: typo and verbous grammar in the grammar spec https://bugs.python.org/issue44257 #44255: strptime and week numbers without week days https://bugs.python.org/issue44255 #44254: Change turtledemo button colors https://bugs.python.org/issue44254 #44251: ctypes '_get_soname' fails silently on missing objdump https://bugs.python.org/issue44251 #44249: Readme typo fix https://bugs.python.org/issue44249 #44245: Cross-compilation of CPython 3.8 with _socket module using And https://bugs.python.org/issue44245 #44239: Use platform defined data directories instead of ~/.python_his https://bugs.python.org/issue44239 #44238: Unable to install Python 3.9.5 - Windows Server https://bugs.python.org/issue44238 #44225: stop() on a stopped loop inhibits the next run_forever https://bugs.python.org/issue44225 #44221: ImportError: sys.meta_path is None, Python is likely shutting https://bugs.python.org/issue44221 #44220: PyStructSequence_UnnamedField unavailable on Windows https://bugs.python.org/issue44220 Most recent 15 issues waiting for review (15) ============================================= #44258: Support PEP 515 for Fraction's initialization from string https://bugs.python.org/issue44258 #44257: typo and verbous grammar in the grammar spec https://bugs.python.org/issue44257 #44249: Readme typo fix https://bugs.python.org/issue44249 #44246: 3.10 beta 1: breaking change in importlib.metadata entry point https://bugs.python.org/issue44246 #44239: Use platform defined data directories instead of ~/.python_his https://bugs.python.org/issue44239 #44235: Remove l*gettext() and related functions in the gettext module https://bugs.python.org/issue44235 #44230: lookup extensions with the stable ABI under a platform specifi https://bugs.python.org/issue44230 #44220: PyStructSequence_UnnamedField unavailable on Windows https://bugs.python.org/issue44220 #44212: asyncio overrides signal handlers https://bugs.python.org/issue44212 #44211: Duplicate '.bmp' key in mimetypes.py, maps to both 'image/bmp' https://bugs.python.org/issue44211 #44210: Make importlib.metadata._meta.PackageMetadata public https://bugs.python.org/issue44210 #44206: Add a version number to dict keys. https://bugs.python.org/issue44206 #44205: shutil.copystat can fail when copying to a file system with a https://bugs.python.org/issue44205 #44195: importlib.abc.TraversableReader is not implemented https://bugs.python.org/issue44195 #44188: ThreadPoolExecutor unbalanced semaphore count https://bugs.python.org/issue44188 Top 10 most discussed issues (10) ================================= #42972: [C API] Heap types (PyType_FromSpec) must fully implement the https://bugs.python.org/issue42972 42 msgs #44242: enum.IntFlag regression: missing values cause TypeError https://bugs.python.org/issue44242 16 msgs #44252: test_ssl and test_httplib.HTTPSTest crash randomly with "Windo https://bugs.python.org/issue44252 15 msgs #44217: Tkinter/IDLE: literal astral char discombobulates text editing https://bugs.python.org/issue44217 14 msgs #44229: Intermittent connection errors in ssl tests on macOS CI https://bugs.python.org/issue44229 13 msgs #43921: test_ssl fails on Windows buildbots https://bugs.python.org/issue43921 12 msgs #44246: 3.10 beta 1: breaking change in importlib.metadata entry point https://bugs.python.org/issue44246 10 msgs #44031: test_embed and test_tabnanny fails if the current directory is https://bugs.python.org/issue44031 9 msgs #37596: Reproducible pyc: frozenset is not serialized in a determinist https://bugs.python.org/issue37596 8 msgs #44206: Add a version number to dict keys. https://bugs.python.org/issue44206 8 msgs Issues closed (76) ================== #3702: test_urllib2.test_trivial fails when run from another Windows https://bugs.python.org/issue3702 closed by iritkatriel #8264: [doc] hasattr doesn't show private (double underscore) attribu https://bugs.python.org/issue8264 closed by kj #12463: Calling SocketServer.shutdown() when server_forever() was not https://bugs.python.org/issue12463 closed by iritkatriel #16533: HPUX: Unable to fork() in thread https://bugs.python.org/issue16533 closed by iritkatriel #20408: memoryview() constructor documentation error https://bugs.python.org/issue20408 closed by berker.peksag #21633: Argparse does not propagate HelpFormatter class to subparsers https://bugs.python.org/issue21633 closed by iritkatriel #23443: XMLRPCLIB Exception uses str not class or instance https://bugs.python.org/issue23443 closed by iritkatriel #23833: email.header.Header folding modifies headers that include semi https://bugs.python.org/issue23833 closed by iritkatriel #26503: argparse with required field , not having new line separator i https://bugs.python.org/issue26503 closed by iritkatriel #26740: tarfile: accessing (listing and extracting) tarball fails with https://bugs.python.org/issue26740 closed by iritkatriel #30757: pyinstaller can be added to docs, py2exe ref can be updated https://bugs.python.org/issue30757 closed by erlendaasland #30849: test_stress_delivery_dependent() of test_signal randomly fails https://bugs.python.org/issue30849 closed by vstinner #31790: double free or corruption (while using smem) https://bugs.python.org/issue31790 closed by iritkatriel #32084: [Security] http.server can be abused to redirect to (almost) a https://bugs.python.org/issue32084 closed by ned.deily #32983: UnicodeDecodeError 'ascii' codec can't decode byte in position https://bugs.python.org/issue32983 closed by iritkatriel #33809: Expose `capture_locals` parameter in `traceback` convenience f https://bugs.python.org/issue33809 closed by iritkatriel #35134: Add a new Include/cpython/ subdirectory for the "CPython API" https://bugs.python.org/issue35134 closed by vstinner #35197: graminit.h defines very generic names like 'stmt' or 'test' https://bugs.python.org/issue35197 closed by vstinner #36128: ResourceReader for FileLoader inconsistently handles path sepa https://bugs.python.org/issue36128 closed by jaraco #36560: test_functools leaks randomly 1 memory block https://bugs.python.org/issue36560 closed by vstinner #36940: Update Py_FrozenMain() for _PyCoreConfig (PEP 587) https://bugs.python.org/issue36940 closed by vstinner #36950: test.support: add an helper to wait for an event with a timeou https://bugs.python.org/issue36950 closed by vstinner #37228: UDP sockets created by create_datagram_endpoint() allow by def https://bugs.python.org/issue37228 closed by ned.deily #37903: IDLE Shell sidebar. https://bugs.python.org/issue37903 closed by terry.reedy #38575: Child process deadlock in subprocess.Popen https://bugs.python.org/issue38575 closed by iritkatriel #39995: test_concurrent_futures: ProcessPoolSpawnExecutorDeadlockTest. https://bugs.python.org/issue39995 closed by vstinner #39996: test_multiprocessing_fork hangs on AMD64 FreeBSD Shared 3.x https://bugs.python.org/issue39996 closed by vstinner #40237: Test code coverage (C) job of Travis CI fails on test_distutil https://bugs.python.org/issue40237 closed by vstinner #40551: PRs should be rebased on top of master before running the buil https://bugs.python.org/issue40551 closed by FFY00 #40695: hashlib: OpenSSL hash detection should obey security policy https://bugs.python.org/issue40695 closed by christian.heimes #40736: better message for re.search TypeError ("expected string or by https://bugs.python.org/issue40736 closed by iritkatriel #41147: Document that redirect_std{out,err} yield the new stream as th https://bugs.python.org/issue41147 closed by iritkatriel #41611: IDLE: problems with completions on Mac https://bugs.python.org/issue41611 closed by taleinat #41736: test_site: test_s_option() failed on AMD64 Windows8.1 Refleaks https://bugs.python.org/issue41736 closed by vstinner #41855: FastPath.zip_children can give duplicate results on Python 3.8 https://bugs.python.org/issue41855 closed by jaraco #42043: zipfile.Path should support inheritance https://bugs.python.org/issue42043 closed by jaraco #43063: zipfile.Path / importlib.resources raises KeyError if a file w https://bugs.python.org/issue43063 closed by jaraco #43109: When using Apple Clang, --with-lto builds should not check for https://bugs.python.org/issue43109 closed by vstinner #43167: Add a note to the macOS installer welcome window about customi https://bugs.python.org/issue43167 closed by ned.deily #43504: Site linked in docs, effbot.org, down https://bugs.python.org/issue43504 closed by mdk #43556: fix attr names for ast.expr and ast.stmt https://bugs.python.org/issue43556 closed by iritkatriel #43643: importlib.readers.MultiplexedPath.name is not a property https://bugs.python.org/issue43643 closed by jaraco #43667: Solaris: Fix broken Unicode encoding in non-UTF locales https://bugs.python.org/issue43667 closed by vstinner #43688: [C API] Support the limited C API in debug mode (Py_INCREF and https://bugs.python.org/issue43688 closed by vstinner #43774: [Doc] Document configure options in the Python documentation https://bugs.python.org/issue43774 closed by vstinner #43843: libregrtest: mark a test as failed if a thread logs an unexpec https://bugs.python.org/issue43843 closed by vstinner #43879: Add native_thread_id to PyThreadState https://bugs.python.org/issue43879 closed by vstinner #43927: Remove IOError references from the tutorial https://bugs.python.org/issue43927 closed by terry.reedy #43988: Add test.support.check_disallow_instantiation() https://bugs.python.org/issue43988 closed by erlendaasland #44010: IDLE: highlight soft keywords https://bugs.python.org/issue44010 closed by taleinat #44032: Function locals and evaluation stack should be stored in a con https://bugs.python.org/issue44032 closed by vstinner #44043: 3.10 b1 armhf Bus Error in hashlib test: test_gil https://bugs.python.org/issue44043 closed by christian.heimes #44120: logging.config.fileConfig/dictConfig can not import class https://bugs.python.org/issue44120 closed by vinay.sajip #44131: [C API] Add tests on Py_FrozenMain() https://bugs.python.org/issue44131 closed by pablogsal #44151: Improve parameter names and return value ordering for linear_r https://bugs.python.org/issue44151 closed by rhettinger #44184: crash on windows invoking flake8 https://bugs.python.org/issue44184 closed by vstinner #44190: Dictionary assignment shorthand https://bugs.python.org/issue44190 closed by terry.reedy #44196: Document that importlib.abc.Traversable's methods should raise https://bugs.python.org/issue44196 closed by FFY00 #44201: REPL requests another line despite syntax error https://bugs.python.org/issue44201 closed by pablogsal #44208: argparse: Accept option without needing to distinguish "-" fro https://bugs.python.org/issue44208 closed by rhettinger #44216: Bug in class method with optional parameter https://bugs.python.org/issue44216 closed by steven.daprano #44222: Improving _removeHandlerRef for a very long _handlerList https://bugs.python.org/issue44222 closed by Yonatan Goldschmidt #44223: := in comprehensions does not work https://bugs.python.org/issue44223 closed by serhiy.storchaka #44224: urllib.parse.urljoin behaves differently in Python 3.9.5 https://bugs.python.org/issue44224 closed by rushter #44227: help(bisect.bisect_left) https://bugs.python.org/issue44227 closed by rhettinger #44228: [urllib] Error with handling of urllib.parse.quote. Terminate https://bugs.python.org/issue44228 closed by martin.panter #44231: Remove _PyTuple_FromArray from the public API https://bugs.python.org/issue44231 closed by vstinner #44232: Crash in Objects/typeobject.c https://bugs.python.org/issue44232 closed by vstinner #44241: Sync importlib_metadata enhancements through 4.1. https://bugs.python.org/issue44241 closed by jaraco #44243: tkinter button colors on Mac https://bugs.python.org/issue44243 closed by terry.reedy #44244: protected members accessible in other modules https://bugs.python.org/issue44244 closed by iritkatriel #44247: bpo stacktrace linkifier does not understand 3.10+ https://bugs.python.org/issue44247 closed by zach.ware #44248: copy.deepcopy calls objdect's __deepcopy__ with incorrect argu https://bugs.python.org/issue44248 closed by zach.ware #44250: Link to ibera IRC goes to 404 page https://bugs.python.org/issue44250 closed by xtreak #44253: tkinter searches for tk.tcl in wrong directory https://bugs.python.org/issue44253 closed by ned.deily #44256: _functools._lru_list_elem is exposed unintentionally. https://bugs.python.org/issue44256 closed by methane

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IRC #python-dev channel is now on Libera Chat (bye bye Freenode)
by Victor Stinner May 27, 2021

May 27, 2021

Hi, The #python-dev IRC channel moves from Freenode to Libera Chat: https://libera.chat/ I'm connected as vstinner, see you there ;-) Join the channel if you would like to talk about the development of Python itself (the VM, bytecode, stdlib, etc.)! Moreover, bots notifications (GitHub, buildbots, bugs.python.org) are now in a new dedicated channel #python-dev-notifs so humans can talk together again! :-) The migration is on-going, right now some notifications are still on Freenode. -- Yesterday evening, Freenode admins decided to take the control of the #python-fr channel on Freenode (which now redirects to a new ##python-fr channel), only because the channel topic contained "libera"! The french Python association ("AFPy") managing #python-fr lost control and decided to migrate to Libera Chat (libera.chat). Announcement in french: https://www.afpy.org/posts/actualites/1622023152 I'm disappointed by how the events are going. At least, it motivated me to move bots notfications ;-) Victor -- Night gathers, and now my watch begins. It shall not end until my death.

9 11

IMPORTANT: Python 3.10b2 release blockers
by Pablo Galindo Salgado May 26, 2021

May 26, 2021

Hi, Tomorrow is the scheduled release of Python 3.10 beta 2 but unfortunately we have several release blockers: https://bugs.python.org/issue41282: Deprecate and remove distutils https://bugs.python.org/issue40222: "Zero cost" exception handling https://bugs.python.org/issue42972: [C API] Heap types (PyType_FromSpec) must fully implement the GC protocol https://bugs.python.org/issue44043: 3.10 b1 armhf Bus Error in hashlib test: test_gil We also have the address sanitizer buildbot failing : https://buildbot.python.org/all/#/builders/582/builds/165/steps/5/logs/stdio and some segmentation faults on the fedora stable buildbot: https://buildbot.python.org/all/#/builders/543/builds/190 Some of these issues have PRs but some of them have not. Please, if you are involved or you maintain one of the areas involved in these issues, take a look at them and act with one of the following: * Fix the issue making a PR * Review an existing PR and / or merge it * If you intend to mark it as a deferred blocker, please provide a rationale and contact me first by pinging me in the issue. Until these issues are fixed or deferred, the release team will not be able to make a new beta release. Thanks for your help, Regards from stormy London, Pablo Galindo Salgado

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Question for potential python development contributions on Windows
by pjfarley3＠earthlink.net May 24, 2021

May 24, 2021

The Python Developers Guide specifically states to get VS2017 for developing or enhancing python on a Windows system. Is it still correct to specifically use VS2017 , or is VS2019 also acceptable? I ask this because I know that the *.vcproj files and other build-environment files have changed format pretty dramatically over the many releases of VS. If a potential new contribution targeted for current and future python will require new build environment files, I wouldn't want to have to "down release" those files (or expect core dev's to do it) at or after submission to the community for approval. Much better to use the same setup as core dev's use than to introduce up-level differences in the build environment. IOW, for new releases on Windows are core dev's still using VS2017 and so potential contributors should also use that version, or has the core dev's process for Windows releases been updated to use VS2019? Peter --

5 5

Summary of Python tracker Issues
by Python tracker May 21, 2021

May 21, 2021

ACTIVITY SUMMARY (2021-05-14 - 2021-05-21) 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 7452 (+23) closed 48492 (+51) total 55944 (+74) Open issues with patches: 2965 Issues opened (57) ================== #39950: Add pathlib.Path.hardlink_to() https://bugs.python.org/issue39950 reopened by barneygale #42834: [subinterpreters] Convert "global" static variable caches in _ https://bugs.python.org/issue42834 reopened by kj #44126: Support cross-compiling of cpython modules using setuptools https://bugs.python.org/issue44126 reopened by jmoguill2 #44135: issubclass documentation doesn't explain tuple semantic https://bugs.python.org/issue44135 opened by joaozinho #44136: Remove pathlib flavours https://bugs.python.org/issue44136 opened by barneygale #44138: multiprocessing documentation should note behavior when proces https://bugs.python.org/issue44138 opened by kushal-kumaran #44140: WeakKeyDictionary should support lookup by id instead of hash https://bugs.python.org/issue44140 opened by conchylicultor #44142: ast.unparse: visually better code generation https://bugs.python.org/issue44142 opened by BTaskaya #44145: hmac.update is not releasing the GIL when openssl's hmac is us https://bugs.python.org/issue44145 opened by gregory.p.smith #44147: [WinError 193] %1 is not a valid Win32 application https://bugs.python.org/issue44147 opened by bassel27 #44149: difflib.get_close_matches: Add `key` argument https://bugs.python.org/issue44149 opened by mustafaquraish #44151: Improve parameter names and return value ordering for linear_r https://bugs.python.org/issue44151 opened by rhettinger #44153: Signaling an asyncio subprocess might raise ProcessLookupError https://bugs.python.org/issue44153 opened by syntaxcoloring #44155: Race condition when using multiprocessing BaseManager and Pool https://bugs.python.org/issue44155 opened by chenzhuowansui #44156: [subinterpreters] Replace static string caches with subinterpr https://bugs.python.org/issue44156 opened by kj #44157: redirect_* should also redirect C-level streams https://bugs.python.org/issue44157 opened by xmorel #44158: Clarify documentation for redirected stdout/stderr when using https://bugs.python.org/issue44158 opened by tanty #44159: mimetypes - "strict" on Windows https://bugs.python.org/issue44159 opened by Norman Lorrain #44163: IDLE ValueError in HyperParser https://bugs.python.org/issue44163 opened by rhettinger #44164: Document what are resources in importlib.resources https://bugs.python.org/issue44164 opened by FFY00 #44165: [sqlite3] sqlite3_prepare_v2 micro optimisation: pass string s https://bugs.python.org/issue44165 opened by erlendaasland #44166: Make IndexError messages for list more informative https://bugs.python.org/issue44166 opened by miguendes #44167: ipaddress.IPv6Address.is_private makes redundant checks https://bugs.python.org/issue44167 opened by mjpieters #44170: ShareableList cannot safely handle multibyte utf-8 characters https://bugs.python.org/issue44170 opened by huwcbjones #44172: curses module may call delwin() on original window before subw https://bugs.python.org/issue44172 opened by michaelforney #44173: Stored (uncompressed) ZipExtFile in zipfile can be seekable at https://bugs.python.org/issue44173 opened by juniorjpdj #44174: Unclear meaning of _Private__names in enum docs. https://bugs.python.org/issue44174 opened by gregory.p.smith #44175: What do "cased" and "uncased" mean? https://bugs.python.org/issue44175 opened by otakutyrant #44176: asyncio.as_completed() raises TypeError when the first supplie https://bugs.python.org/issue44176 opened by alexdelorenzo #44178: Add an interpreter-level critical section construct https://bugs.python.org/issue44178 opened by xmorel #44180: SyntaxError misidentified in 3.10.0b1 when = used instead of : https://bugs.python.org/issue44180 opened by aroberge #44181: SyntaxError in Python 3.10.0b1: wrong token for missing comma https://bugs.python.org/issue44181 opened by aroberge #44182: python-config.sh vs python-config.py inconsistency https://bugs.python.org/issue44182 opened by millert #44183: Can't install certificates if GUI tools are not installed on m https://bugs.python.org/issue44183 opened by thetechconspiracy #44184: crash on windows invoking flake8 https://bugs.python.org/issue44184 opened by Anthony Sottile #44185: mock_open file handle __exit__ does not call close https://bugs.python.org/issue44185 opened by williamsjoblom #44186: TimedRotatingFileHandler overwrite log https://bugs.python.org/issue44186 opened by aeg #44187: Implement infrastructure for quickening and specializing https://bugs.python.org/issue44187 opened by Mark.Shannon #44188: ThreadPoolExecutor unbalanced semaphore count https://bugs.python.org/issue44188 opened by bennieswart #44189: multiprocessing AF_PIPE name format is slightly confusing in t https://bugs.python.org/issue44189 opened by Antony.Lee #44190: Dictionary assignment shorthand https://bugs.python.org/issue44190 opened by davidhariri #44191: Getting an ImportError DLL load failed while importing _ssl https://bugs.python.org/issue44191 opened by lnegger #44192: Annotations, Inheritance and Circular Reference https://bugs.python.org/issue44192 opened by reob-info #44193: socket line 46 import _socket Import Error https://bugs.python.org/issue44193 opened by Joshex #44194: Folding ''.join(<known number of elts>) into f-strings https://bugs.python.org/issue44194 opened by BTaskaya #44195: importlib.abc.TraversableReader is not implemented https://bugs.python.org/issue44195 opened by FFY00 #44196: Document that importlib.abc.Traversable's methods should raise https://bugs.python.org/issue44196 opened by FFY00 #44198: Add flags or function in pathlib.Path https://bugs.python.org/issue44198 opened by tetelevm #44200: Recommend importlib.abc.Traversable users to implement __fspat https://bugs.python.org/issue44200 opened by FFY00 #44201: REPL requests another line despite syntax error https://bugs.python.org/issue44201 opened by gvanrossum #44202: Add errors argument to importlib.abc.Traversable.read_text https://bugs.python.org/issue44202 opened by FFY00 #44203: test__xxsubinterpreters: heap-buffer-overflow in interp_is_run https://bugs.python.org/issue44203 opened by vstinner #44204: socket.connect ignores CTRL+C during timeout on Win https://bugs.python.org/issue44204 opened by mrx23dot #44205: shutil.copystat can fail when copying to a file system with a https://bugs.python.org/issue44205 opened by chrisburr #44206: Add a version number to dict keys. https://bugs.python.org/issue44206 opened by Mark.Shannon #44207: Add a version number to Python functions https://bugs.python.org/issue44207 opened by Mark.Shannon #44208: argparse: Accept option without needing to distinguish "-" fro https://bugs.python.org/issue44208 opened by wbarnha Most recent 15 issues with no replies (15) ========================================== #44208: argparse: Accept option without needing to distinguish "-" fro https://bugs.python.org/issue44208 #44207: Add a version number to Python functions https://bugs.python.org/issue44207 #44205: shutil.copystat can fail when copying to a file system with a https://bugs.python.org/issue44205 #44204: socket.connect ignores CTRL+C during timeout on Win https://bugs.python.org/issue44204 #44203: test__xxsubinterpreters: heap-buffer-overflow in interp_is_run https://bugs.python.org/issue44203 #44198: Add flags or function in pathlib.Path https://bugs.python.org/issue44198 #44196: Document that importlib.abc.Traversable's methods should raise https://bugs.python.org/issue44196 #44195: importlib.abc.TraversableReader is not implemented https://bugs.python.org/issue44195 #44192: Annotations, Inheritance and Circular Reference https://bugs.python.org/issue44192 #44188: ThreadPoolExecutor unbalanced semaphore count https://bugs.python.org/issue44188 #44187: Implement infrastructure for quickening and specializing https://bugs.python.org/issue44187 #44186: TimedRotatingFileHandler overwrite log https://bugs.python.org/issue44186 #44185: mock_open file handle __exit__ does not call close https://bugs.python.org/issue44185 #44183: Can't install certificates if GUI tools are not installed on m https://bugs.python.org/issue44183 #44182: python-config.sh vs python-config.py inconsistency https://bugs.python.org/issue44182 Most recent 15 issues waiting for review (15) ============================================= #44208: argparse: Accept option without needing to distinguish "-" fro https://bugs.python.org/issue44208 #44205: shutil.copystat can fail when copying to a file system with a https://bugs.python.org/issue44205 #44196: Document that importlib.abc.Traversable's methods should raise https://bugs.python.org/issue44196 #44195: importlib.abc.TraversableReader is not implemented https://bugs.python.org/issue44195 #44188: ThreadPoolExecutor unbalanced semaphore count https://bugs.python.org/issue44188 #44187: Implement infrastructure for quickening and specializing https://bugs.python.org/issue44187 #44184: crash on windows invoking flake8 https://bugs.python.org/issue44184 #44180: SyntaxError misidentified in 3.10.0b1 when = used instead of : https://bugs.python.org/issue44180 #44173: Stored (uncompressed) ZipExtFile in zipfile can be seekable at https://bugs.python.org/issue44173 #44172: curses module may call delwin() on original window before subw https://bugs.python.org/issue44172 #44167: ipaddress.IPv6Address.is_private makes redundant checks https://bugs.python.org/issue44167 #44166: Make IndexError messages for list more informative https://bugs.python.org/issue44166 #44165: [sqlite3] sqlite3_prepare_v2 micro optimisation: pass string s https://bugs.python.org/issue44165 #44164: Document what are resources in importlib.resources https://bugs.python.org/issue44164 #44156: [subinterpreters] Replace static string caches with subinterpr https://bugs.python.org/issue44156 Top 10 most discussed issues (10) ================================= #44184: crash on windows invoking flake8 https://bugs.python.org/issue44184 32 msgs #40452: Tkinter/IDLE: preserve clipboard on closure https://bugs.python.org/issue40452 19 msgs #44151: Improve parameter names and return value ordering for linear_r https://bugs.python.org/issue44151 13 msgs #44099: [C API] Introduce a new slot in PyModuleDef to hold the classe https://bugs.python.org/issue44099 10 msgs #44147: [WinError 193] %1 is not a valid Win32 application https://bugs.python.org/issue44147 10 msgs #28937: str.split(): allow removing empty strings (when sep is not Non https://bugs.python.org/issue28937 9 msgs #44180: SyntaxError misidentified in 3.10.0b1 when = used instead of : https://bugs.python.org/issue44180 8 msgs #43882: [security] urllib.parse should sanitize urls containing ASCII https://bugs.python.org/issue43882 7 msgs #44175: What do "cased" and "uncased" mean? https://bugs.python.org/issue44175 6 msgs #42109: Use hypothesis for testing the standard library, falling back https://bugs.python.org/issue42109 5 msgs Issues closed (48) ================== #22891: code removal from urllib.parse.urlsplit() https://bugs.python.org/issue22891 closed by gregory.p.smith #29639: test suite intentionally avoids referring to localhost, destro https://bugs.python.org/issue29639 closed by gregory.p.smith #30593: Document that sqlite3.Cursor.executescript disregards isolatio https://bugs.python.org/issue30593 closed by berker.peksag #32133: documentation: numbers module nitpick https://bugs.python.org/issue32133 closed by rhettinger #33433: ipaddress is_private misleading for IPv4 mapped IPv6 addresses https://bugs.python.org/issue33433 closed by gregory.p.smith #35765: Document references object x but doesn't show it in the exampl https://bugs.python.org/issue35765 closed by iritkatriel #35889: sqlite3.Row doesn't have useful repr https://bugs.python.org/issue35889 closed by berker.peksag #36160: Multiple errors in test_site.py on sysconfig._CONFIG_VARS.clea https://bugs.python.org/issue36160 closed by iritkatriel #36464: Python 2.7 build install fails intermittently with -j on MacOS https://bugs.python.org/issue36464 closed by willingc #38593: Python 3.7 does not catch infinite recursion for some values o https://bugs.python.org/issue38593 closed by iritkatriel #39924: pathlib handles missing `os.link`, `os.symlink` and `os.readli https://bugs.python.org/issue39924 closed by barneygale #40339: Instead of skipping, IPV6 test(s) fail on a non-IPV6 machine https://bugs.python.org/issue40339 closed by gregory.p.smith #40670: supplying an empty string to timeit causes an IndentationError https://bugs.python.org/issue40670 closed by iritkatriel #40975: contextlib.AsyncExitStack enter_async_context and aclose shoul https://bugs.python.org/issue40975 closed by iritkatriel #41318: Better error message of "Cannot recover from stack overflow." https://bugs.python.org/issue41318 closed by iritkatriel #42022: Allow ensurepip to work without bundled wheels https://bugs.python.org/issue42022 closed by FFY00 #42783: asyncio.sleep(0) idiom is not documented https://bugs.python.org/issue42783 closed by iritkatriel #43295: datetime.strptime emits IndexError on parsing 'z' as %z https://bugs.python.org/issue43295 closed by vstinner #43650: MemoryError on zip.read in shutil._unpack_zipfile https://bugs.python.org/issue43650 closed by gregory.p.smith #43753: [C API] Add Py_Is(x, y) and Py_IsNone(x) functions https://bugs.python.org/issue43753 closed by vstinner #44038: In documentation Section 8.6, the definition of parameter_list https://bugs.python.org/issue44038 closed by pablogsal #44072: Doc: power operator (`**`) present for numbers.Complex, not ad https://bugs.python.org/issue44072 closed by terry.reedy #44078: Output relative path when using PurePath.relative_to https://bugs.python.org/issue44078 closed by terry.reedy #44081: ast.unparse: dont use redundant space separator for lambdas wi https://bugs.python.org/issue44081 closed by BTaskaya #44086: py.svg not found on search result page https://bugs.python.org/issue44086 closed by jugmac00 #44106: [sqlite3] don't use politicians in examples/docs https://bugs.python.org/issue44106 closed by erlendaasland #44107: HTTPServer can't close http client completely https://bugs.python.org/issue44107 closed by gregory.p.smith #44132: Local import conflict with system import https://bugs.python.org/issue44132 closed by ned.deily #44137: importlib.resources.path raises RuntimeError when FileNotFound https://bugs.python.org/issue44137 closed by jaraco #44139: Unparenthesized tuple doc bug in what's new https://bugs.python.org/issue44139 closed by pablogsal #44141: Getting error while importing ssl "import _ssl ImportError: DL https://bugs.python.org/issue44141 closed by christian.heimes #44143: The parse crashes when raising tokenizer errors when an existi https://bugs.python.org/issue44143 closed by pablogsal #44144: Python window not opening https://bugs.python.org/issue44144 closed by christian.heimes #44146: Format string fill not handling brace char https://bugs.python.org/issue44146 closed by eric.smith #44148: Raise a SystemError if frame is NULL in PyEval_GetGlobals https://bugs.python.org/issue44148 closed by shreyanavigyan #44150: Add optional weights parameter to statistics.fmean() https://bugs.python.org/issue44150 closed by rhettinger #44152: [not a bug] .isupper() does not support Polytonic Greek (but . https://bugs.python.org/issue44152 closed by Jelle Zijlstra #44154: Optimize Fraction pickling https://bugs.python.org/issue44154 closed by Sergey.Kirpichev #44160: speed up searching for keywords by using a dictionary https://bugs.python.org/issue44160 closed by Dennis Sweeney #44161: free: invalid pointer on graph and photo.message imports https://bugs.python.org/issue44161 closed by christian.heimes #44162: importlib.resources.path no longer supports directories https://bugs.python.org/issue44162 closed by gitpushdashf #44168: Wrong syntax error hint when spurious colon present in functio https://bugs.python.org/issue44168 closed by pablogsal #44169: Add HTTPS support to http.server https://bugs.python.org/issue44169 closed by ned.deily #44171: Cython cannot compile 'a = 5/6' and return 'a = 0' https://bugs.python.org/issue44171 closed by pablogsal #44177: Unable to get the else while parsing through AST module https://bugs.python.org/issue44177 closed by eric.smith #44179: python3 �� range�� https://bugs.python.org/issue44179 closed by christian.heimes #44197: [request feature] Itertools extended combinations to limited n https://bugs.python.org/issue44197 closed by rhettinger #44199: code example index error in tutorial controlflow https://bugs.python.org/issue44199 closed by HVoltBb

1 0

Critique of PEP 657 -- Include Fine Grained Error Locations in Tracebacks
by Mark Shannon May 21, 2021

May 21, 2021

Hi everyone, I fully agree with the rationale for the PEP, better error messages always help. However, I think the proposed implementation could be misleading in some cases and wastes memory. Use one position, not one-and-a-half positions. ----------------------------------------------- The main problem with PEP 657, IMO, is that it wants to present the location of an error as a pair of positions, but without the line number of the second position. Consequently it ends up with one and a half positions, not two. This does not work well for a number of reasons. 1. Errors spanning multiple lines. Consider: (i1 + i2 + s1 ) Where i1, i2 are integers and s1 is a string. With a single location, the error points to the second `+`. PEP 657 would highlight the whole line, `i1 + i2 +`, making it unclear where the error occurred. 2. Repeated binary operations on the same line. A single location can also be clearer when all the code is on one line. i1 + i2 + s1 PEP 657: i1 + i2 + s1 ^^^^^^^^^^^^ Using a single location: i1 + i2 + s1 ^ 3. Tracking locations in the compiler. While nicer locations for errors is great, it won't be popular if it has a negative impact on performance. Locations need to tracked through the compiler. The simpler the location, the easier this is to do correctly without a negative performance impact. It is already tricky to do this correctly with just line numbers because we have both source that compiles to no bytecodes (try, pass) and bytecodes that have no source (implicit return None and except cleanups). A single location can still be presented as a whole token, as tokenizing a single line of code is easy and fast. So when presenting an error, the whole token can be highlighted. E.g: NameError name ^^^^ Compression ----------- PEP 657 proposes that no compression be used, but also mandates the use of a lossy compression scheme (truncating all offsets over 255). I think it would be better to provide an API like PEP 626 and not restrict the internal format used. In fact, extending or replacing the API of PEP 626 seems the best approach to me. I wouldn't worry about memory consumption. The code object layout and unmarshalling process needs to be re-implemented for reduced memory use and faster startup: https://github.com/markshannon/faster-cpython/blob/master/tiers.md#tier-0 A few bytes more or less in the location table(s) is inconsequential. Cheers, Mark.

8 19

Speeding up CPython
by Mark Shannon May 18, 2021

May 18, 2021

Hi everyone, CPython is slow. We all know that, yet little is done to fix it. I'd like to change that. I have a plan to speed up CPython by a factor of five over the next few years. But it needs funding. I am aware that there have been several promised speed ups in the past that have failed. You might wonder why this is different. Here are three reasons: 1. I already have working code for the first stage. 2. I'm not promising a silver bullet. I recognize that this is a substantial amount of work and needs funding. 3. I have extensive experience in VM implementation, not to mention a PhD in the subject. My ideas for possible funding, as well as the actual plan of development, can be found here: https://github.com/markshannon/faster-cpython I'd love to hear your thoughts on this. Cheers, Mark.

33 77

PEP 1, PEP Purpose and Guidelines
by barry＠zope.com May 18, 2021

May 18, 2021

It has been a while since I posted a copy of PEP 1 to the mailing lists and newsgroups. I've recently done some updating of a few sections, so in the interest of gaining wider community participation in the Python development process, I'm posting the latest revision of PEP 1 here. A version of the PEP is always available on-line at http://www.python.org/peps/pep-0001.html Enjoy, -Barry -------------------- snip snip -------------------- PEP: 1 Title: PEP Purpose and Guidelines Version: $Revision: 1.36 $ Last-Modified: $Date: 2002/07/29 18:34:59 $ Author: Barry A. Warsaw, Jeremy Hylton Status: Active Type: Informational Created: 13-Jun-2000 Post-History: 21-Mar-2001, 29-Jul-2002 What is a PEP? PEP stands for Python Enhancement Proposal. A PEP is a design document providing information to the Python community, or describing a new feature for Python. The PEP should provide a concise technical specification of the feature and a rationale for the feature. We intend PEPs to be the primary mechanisms for proposing new features, for collecting community input on an issue, and for documenting the design decisions that have gone into Python. The PEP author is responsible for building consensus within the community and documenting dissenting opinions. Because the PEPs are maintained as plain text files under CVS control, their revision history is the historical record of the feature proposal[1]. Kinds of PEPs There are two kinds of PEPs. A standards track PEP describes a new feature or implementation for Python. An informational PEP describes a Python design issue, or provides general guidelines or information to the Python community, but does not propose a new feature. Informational PEPs do not necessarily represent a Python community consensus or recommendation, so users and implementors are free to ignore informational PEPs or follow their advice. PEP Work Flow The PEP editor, Barry Warsaw <peps(a)python.org>, assigns numbers for each PEP and changes its status. The PEP process begins with a new idea for Python. It is highly recommended that a single PEP contain a single key proposal or new idea. The more focussed the PEP, the more successfully it tends to be. The PEP editor reserves the right to reject PEP proposals if they appear too unfocussed or too broad. If in doubt, split your PEP into several well-focussed ones. Each PEP must have a champion -- someone who writes the PEP using the style and format described below, shepherds the discussions in the appropriate forums, and attempts to build community consensus around the idea. The PEP champion (a.k.a. Author) should first attempt to ascertain whether the idea is PEP-able. Small enhancements or patches often don't need a PEP and can be injected into the Python development work flow with a patch submission to the SourceForge patch manager[2] or feature request tracker[3]. The PEP champion then emails the PEP editor <peps(a)python.org> with a proposed title and a rough, but fleshed out, draft of the PEP. This draft must be written in PEP style as described below. If the PEP editor approves, he will assign the PEP a number, label it as standards track or informational, give it status 'draft', and create and check-in the initial draft of the PEP. The PEP editor will not unreasonably deny a PEP. Reasons for denying PEP status include duplication of effort, being technically unsound, not providing proper motivation or addressing backwards compatibility, or not in keeping with the Python philosophy. The BDFL (Benevolent Dictator for Life, Guido van Rossum) can be consulted during the approval phase, and is the final arbitrator of the draft's PEP-ability. If a pre-PEP is rejected, the author may elect to take the pre-PEP to the comp.lang.python newsgroup (a.k.a. python-list(a)python.org mailing list) to help flesh it out, gain feedback and consensus from the community at large, and improve the PEP for re-submission. The author of the PEP is then responsible for posting the PEP to the community forums, and marshaling community support for it. As updates are necessary, the PEP author can check in new versions if they have CVS commit permissions, or can email new PEP versions to the PEP editor for committing. Standards track PEPs consists of two parts, a design document and a reference implementation. The PEP should be reviewed and accepted before a reference implementation is begun, unless a reference implementation will aid people in studying the PEP. Standards Track PEPs must include an implementation - in the form of code, patch, or URL to same - before it can be considered Final. PEP authors are responsible for collecting community feedback on a PEP before submitting it for review. A PEP that has not been discussed on python-list(a)python.org and/or python-dev(a)python.org will not be accepted. However, wherever possible, long open-ended discussions on public mailing lists should be avoided. Strategies to keep the discussions efficient include, setting up a separate SIG mailing list for the topic, having the PEP author accept private comments in the early design phases, etc. PEP authors should use their discretion here. Once the authors have completed a PEP, they must inform the PEP editor that it is ready for review. PEPs are reviewed by the BDFL and his chosen consultants, who may accept or reject a PEP or send it back to the author(s) for revision. Once a PEP has been accepted, the reference implementation must be completed. When the reference implementation is complete and accepted by the BDFL, the status will be changed to `Final.' A PEP can also be assigned status `Deferred.' The PEP author or editor can assign the PEP this status when no progress is being made on the PEP. Once a PEP is deferred, the PEP editor can re-assign it to draft status. A PEP can also be `Rejected'. Perhaps after all is said and done it was not a good idea. It is still important to have a record of this fact. PEPs can also be replaced by a different PEP, rendering the original obsolete. This is intended for Informational PEPs, where version 2 of an API can replace version 1. PEP work flow is as follows: Draft -> Accepted -> Final -> Replaced ^ +----> Rejected v Deferred Some informational PEPs may also have a status of `Active' if they are never meant to be completed. E.g. PEP 1. What belongs in a successful PEP? Each PEP should have the following parts: 1. Preamble -- RFC822 style headers containing meta-data about the PEP, including the PEP number, a short descriptive title (limited to a maximum of 44 characters), the names, and optionally the contact info for each author, etc. 2. Abstract -- a short (~200 word) description of the technical issue being addressed. 3. Copyright/public domain -- Each PEP must either be explicitly labelled as placed in the public domain (see this PEP as an example) or licensed under the Open Publication License[4]. 4. Specification -- The technical specification should describe the syntax and semantics of any new language feature. The specification should be detailed enough to allow competing, interoperable implementations for any of the current Python platforms (CPython, JPython, Python .NET). 5. Motivation -- The motivation is critical for PEPs that want to change the Python language. It should clearly explain why the existing language specification is inadequate to address the problem that the PEP solves. PEP submissions without sufficient motivation may be rejected outright. 6. Rationale -- The rationale fleshes out the specification by describing what motivated the design and why particular design decisions were made. It should describe alternate designs that were considered and related work, e.g. how the feature is supported in other languages. The rationale should provide evidence of consensus within the community and discuss important objections or concerns raised during discussion. 7. Backwards Compatibility -- All PEPs that introduce backwards incompatibilities must include a section describing these incompatibilities and their severity. The PEP must explain how the author proposes to deal with these incompatibilities. PEP submissions without a sufficient backwards compatibility treatise may be rejected outright. 8. Reference Implementation -- The reference implementation must be completed before any PEP is given status 'Final,' but it need not be completed before the PEP is accepted. It is better to finish the specification and rationale first and reach consensus on it before writing code. The final implementation must include test code and documentation appropriate for either the Python language reference or the standard library reference. PEP Template PEPs are written in plain ASCII text, and should adhere to a rigid style. There is a Python script that parses this style and converts the plain text PEP to HTML for viewing on the web[5]. PEP 9 contains a boilerplate[7] template you can use to get started writing your PEP. Each PEP must begin with an RFC822 style header preamble. The headers must appear in the following order. Headers marked with `*' are optional and are described below. All other headers are required. PEP: <pep number> Title: <pep title> Version: <cvs version string> Last-Modified: <cvs date string> Author: <list of authors' real names and optionally, email addrs> * Discussions-To: <email address> Status: <Draft | Active | Accepted | Deferred | Final | Replaced> Type: <Informational | Standards Track> * Requires: <pep numbers> Created: <date created on, in dd-mmm-yyyy format> * Python-Version: <version number> Post-History: <dates of postings to python-list and python-dev> * Replaces: <pep number> * Replaced-By: <pep number> The Author: header lists the names and optionally, the email addresses of all the authors/owners of the PEP. The format of the author entry should be address(a)dom.ain (Random J. User) if the email address is included, and just Random J. User if the address is not given. If there are multiple authors, each should be on a separate line following RFC 822 continuation line conventions. Note that personal email addresses in PEPs will be obscured as a defense against spam harvesters. Standards track PEPs must have a Python-Version: header which indicates the version of Python that the feature will be released with. Informational PEPs do not need a Python-Version: header. While a PEP is in private discussions (usually during the initial Draft phase), a Discussions-To: header will indicate the mailing list or URL where the PEP is being discussed. No Discussions-To: header is necessary if the PEP is being discussed privately with the author, or on the python-list or python-dev email mailing lists. Note that email addresses in the Discussions-To: header will not be obscured. Created: records the date that the PEP was assigned a number, while Post-History: is used to record the dates of when new versions of the PEP are posted to python-list and/or python-dev. Both headers should be in dd-mmm-yyyy format, e.g. 14-Aug-2001. PEPs may have a Requires: header, indicating the PEP numbers that this PEP depends on. PEPs may also have a Replaced-By: header indicating that a PEP has been rendered obsolete by a later document; the value is the number of the PEP that replaces the current document. The newer PEP must have a Replaces: header containing the number of the PEP that it rendered obsolete. PEP Formatting Requirements PEP headings must begin in column zero and the initial letter of each word must be capitalized as in book titles. Acronyms should be in all capitals. The body of each section must be indented 4 spaces. Code samples inside body sections should be indented a further 4 spaces, and other indentation can be used as required to make the text readable. You must use two blank lines between the last line of a section's body and the next section heading. You must adhere to the Emacs convention of adding two spaces at the end of every sentence. You should fill your paragraphs to column 70, but under no circumstances should your lines extend past column 79. If your code samples spill over column 79, you should rewrite them. Tab characters must never appear in the document at all. A PEP should include the standard Emacs stanza included by example at the bottom of this PEP. A PEP must contain a Copyright section, and it is strongly recommended to put the PEP in the public domain. When referencing an external web page in the body of a PEP, you should include the title of the page in the text, with a footnote reference to the URL. Do not include the URL in the body text of the PEP. E.g. Refer to the Python Language web site [1] for more details. ... [1] http://www.python.org When referring to another PEP, include the PEP number in the body text, such as "PEP 1". The title may optionally appear. Add a footnote reference that includes the PEP's title and author. It may optionally include the explicit URL on a separate line, but only in the References section. Note that the pep2html.py script will calculate URLs automatically, e.g.: ... Refer to PEP 1 [7] for more information about PEP style ... References [7] PEP 1, PEP Purpose and Guidelines, Warsaw, Hylton http://www.python.org/peps/pep-0001.html If you decide to provide an explicit URL for a PEP, please use this as the URL template: http://www.python.org/peps/pep-xxxx.html PEP numbers in URLs must be padded with zeros from the left, so as to be exactly 4 characters wide, however PEP numbers in text are never padded. Reporting PEP Bugs, or Submitting PEP Updates How you report a bug, or submit a PEP update depends on several factors, such as the maturity of the PEP, the preferences of the PEP author, and the nature of your comments. For the early draft stages of the PEP, it's probably best to send your comments and changes directly to the PEP author. For more mature, or finished PEPs you may want to submit corrections to the SourceForge bug manager[6] or better yet, the SourceForge patch manager[2] so that your changes don't get lost. If the PEP author is a SF developer, assign the bug/patch to him, otherwise assign it to the PEP editor. When in doubt about where to send your changes, please check first with the PEP author and/or PEP editor. PEP authors who are also SF committers, can update the PEPs themselves by using "cvs commit" to commit their changes. Remember to also push the formatted PEP text out to the web by doing the following: % python pep2html.py -i NUM where NUM is the number of the PEP you want to push out. See % python pep2html.py --help for details. Transferring PEP Ownership It occasionally becomes necessary to transfer ownership of PEPs to a new champion. In general, we'd like to retain the original author as a co-author of the transferred PEP, but that's really up to the original author. A good reason to transfer ownership is because the original author no longer has the time or interest in updating it or following through with the PEP process, or has fallen off the face of the 'net (i.e. is unreachable or not responding to email). A bad reason to transfer ownership is because you don't agree with the direction of the PEP. We try to build consensus around a PEP, but if that's not possible, you can always submit a competing PEP. If you are interested assuming ownership of a PEP, send a message asking to take over, addressed to both the original author and the PEP editor <peps(a)python.org>. If the original author doesn't respond to email in a timely manner, the PEP editor will make a unilateral decision (it's not like such decisions can be reversed. :). References and Footnotes [1] This historical record is available by the normal CVS commands for retrieving older revisions. For those without direct access to the CVS tree, you can browse the current and past PEP revisions via the SourceForge web site at http://cvs.sourceforge.net/cgi-bin/cvsweb.cgi/python/nondist/peps/?cvsroot=… [2] http://sourceforge.net/tracker/?group_id=5470&atid=305470 [3] http://sourceforge.net/tracker/?atid=355470&group_id=5470&func=browse [4] http://www.opencontent.org/openpub/ [5] The script referred to here is pep2html.py, which lives in the same directory in the CVS tree as the PEPs themselves. Try "pep2html.py --help" for details. The URL for viewing PEPs on the web is http://www.python.org/peps/ [6] http://sourceforge.net/tracker/?group_id=5470&atid=305470 [7] PEP 9, Sample PEP Template http://www.python.org/peps/pep-0009.html Copyright This document has been placed in the public domain. Local Variables: mode: indented-text indent-tabs-mode: nil sentence-end-double-space: t fill-column: 70 End:

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Using FutureWarning for last version before deletion.
by Inada Naoki May 16, 2021

May 16, 2021

Hi, folks. Now Python 3.11 development is open and I am removing some deprecated stuffs carefully. I am considering `configparser.ParseError.filename` property that is deprecated since Python 3.2. https://github.com/python/cpython/blob/8e8307d70bb9dc18cfeeed3277c076309b27… My random thoughts about it: * It has been deprecated long enough. * But the maintenance burden is low enough. * If we don't remove long deprecated stuff like this, Python 4.0 will be a big breaking change. My proposal: * Change DeprecationWarning to FutureWarning and wait one more version. * DeprecationWarning is suppressed by default to hide noise from end users. * But sudden breaking change is more annoying to end users. I am not proposing to change PEP 387 "Backwards Compatibility Policy". This is just a new convention. Another idea: * Stop suppressing DeprecationWarning by default * Use at least one PendingDeprecationWarning and one DeprecationWarning. * More than two PendingDeprecationWarning periods is preferred. How do you think? -- Inada Naoki <songofacandy(a)gmail.com>

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