1.. bpo: 45121 2.. date: 2021-09-07-17-10-16 3.. nonce: iG-Hsf 4.. release date: 2021-10-04 5.. section: Core and Builtins 6 7Fix issue where ``Protocol.__init__`` raises ``RecursionError`` when it's 8called directly or via ``super()``. Patch provided by Yurii Karabas. 9 10.. 11 12.. bpo: 45234 13.. date: 2021-09-17-11-20-55 14.. nonce: qUcTVt 15.. section: Library 16 17Fixed a regression in :func:`~shutil.copyfile`, :func:`~shutil.copy`, 18:func:`~shutil.copy2` raising :exc:`FileNotFoundError` when source is a 19directory, which should raise :exc:`IsADirectoryError` 20 21.. 22 23.. bpo: 45216 24.. date: 2021-09-18-13-45-19 25.. nonce: o56nyt 26.. section: Documentation 27 28Remove extra documentation listing methods in ``difflib``. It was rendering 29twice in pydoc and was outdated in some places. 30 31.. 32 33.. bpo: 45024 34.. date: 2021-09-08-17-20-19 35.. nonce: dkNPNi 36.. section: Documentation 37 38:mod:`collections.abc` documentation has been expanded to explicitly cover 39how instance and subclass checks work, with additional doctest examples and 40an exhaustive list of ABCs which test membership purely by presence of the 41right :term:`special method`\s. Patch by Raymond Hettinger. 42 43.. 44 45.. bpo: 45128 46.. date: 2021-09-16-17-22-35 47.. nonce: Jz6fl2 48.. section: Tests 49 50Fix ``test_multiprocessing_fork`` failure due to ``test_logging`` and 51``sys.modules`` manipulation. 52 53.. 54 55.. bpo: 44860 56.. date: 2021-09-08-13-01-37 57.. nonce: qXd0kx 58.. section: Tests 59 60Update ``test_sysconfig.test_user_similar()`` for the posix_user scheme: 61``platlib`` doesn't use :data:`sys.platlibdir`. Patch by Victor Stinner. 62 63.. 64 65.. bpo: 45067 66.. date: 2021-09-09-16-45-26 67.. nonce: mFmY92 68.. section: Build 69 70The ncurses function extended_color_content was introduced in 2017 71 72(https://invisible-island.net/ncurses/NEWS.html#index-t20170401). The 73 74ncurses-devel package in CentOS 7 had a older version ncurses resulted in 75compilation error. For compiling ncurses with extended color support, we 76verify the version of the ncurses library >= 20170401. 77 78.. 79 80.. bpo: 45193 81.. date: 2021-09-15-03-20-06 82.. nonce: G61_GV 83.. section: IDLE 84 85Make completion boxes appear on Ubuntu again. 86 87.. 88 89.. bpo: 45307 90.. date: 2021-09-28-12-00-55 91.. nonce: 3ETFfX 92.. section: C API 93 94Restore the private C API function :func:`_PyImport_FindExtensionObject`. It 95will be removed in Python 3.11. 96