**************************** What's New In Python 3.14 **************************** :Editor: TBD .. Rules for maintenance: * Anyone can add text to this document. Do not spend very much time on the wording of your changes, because your text will probably get rewritten to some degree. * The maintainer will go through Misc/NEWS periodically and add changes; it's therefore more important to add your changes to Misc/NEWS than to this file. * This is not a complete list of every single change; completeness is the purpose of Misc/NEWS. Some changes I consider too small or esoteric to include. If such a change is added to the text, I'll just remove it. (This is another reason you shouldn't spend too much time on writing your addition.) * If you want to draw your new text to the attention of the maintainer, add 'XXX' to the beginning of the paragraph or section. * It's OK to just add a fragmentary note about a change. For example: "XXX Describe the transmogrify() function added to the socket module." The maintainer will research the change and write the necessary text. * You can comment out your additions if you like, but it's not necessary (especially when a final release is some months away). * Credit the author of a patch or bugfix. Just the name is sufficient; the e-mail address isn't necessary. * It's helpful to add the issue number as a comment: XXX Describe the transmogrify() function added to the socket module. (Contributed by P.Y. Developer in :gh:`12345`.) This saves the maintainer the effort of going through the VCS log when researching a change. This article explains the new features in Python 3.14, compared to 3.13. For full details, see the :ref:`changelog `. .. note:: Prerelease users should be aware that this document is currently in draft form. It will be updated substantially as Python 3.14 moves towards release, so it's worth checking back even after reading earlier versions. Summary -- Release highlights ============================= .. This section singles out the most important changes in Python 3.14. Brevity is key. .. PEP-sized items next. New Features ============ Other Language Changes ====================== New Modules =========== * None yet. Improved Modules ================ Optimizations ============= Deprecated ========== Removed ======= argparse -------- * The *type*, *choices*, and *metavar* parameters of :class:`!argparse.BooleanOptionalAction` are removed. They were deprecated since 3.12. email ----- * The *isdst* parameter has been removed from :func:`email.utils.localtime`. (Contributed by Hugo van Kemenade in :gh:`118798`.) pathlib ------- * Remove support for passing additional positional arguments to :meth:`pathlib.PurePath.relative_to` and :meth:`~pathlib.PurePath.is_relative_to`. In previous versions, any such arguments are joined onto *other*. Others ------ * Using :data:`NotImplemented` in a boolean context will now raise a :exc:`TypeError`. It had previously raised a :exc:`DeprecationWarning` since Python 3.9. (Contributed by Jelle Zijlstra in :gh:`118767`.) * :class:`!typing.ByteString` and :class:`!collections.abc.ByteString` are removed. They had previously raised a :exc:`DeprecationWarning` since Python 3.12. * :mod:`itertools` support for copy, deepcopy, and pickle operations. These had previously raised a :exc:`DeprecationWarning` since Python 3.12. (Contributed by Raymond Hettinger in :gh:`101588`.) Porting to Python 3.14 ====================== This section lists previously described changes and other bugfixes that may require changes to your code. Build Changes ============= C API Changes ============= New Features ------------ Porting to Python 3.14 ---------------------- Deprecated ---------- Removed -------