Sync pre-release CPython 3.15 branch from GitHub (2026-08-21)

Summary:
Imported python/cpython `3.15.0rc1+dev` from upstream rev [`f71fbc5`](https://www.github.com/python/cpython/commit/f71fbc558a3051781297106f53820b04c217c13d) (committed 2026-08-21 01:40:43+00:00).

# Commit Info

- Base: (`3.15.0rc1+dev`) - [`93404ce`](https://www.github.com/python/cpython/commit/93404cebd972cd85a6adfa1af3acf61b74de56eb) (commit date: 2026-08-20 00:54:11+00:00)
- Imported: (`3.15.0rc1+dev`) - [`f71fbc5`](https://www.github.com/python/cpython/commit/f71fbc558a3051781297106f53820b04c217c13d) (commit date: 2026-08-21 01:40:43+00:00)

Differential Revision: D116894838

fbshipit-source-id: da6bc3594413e343c88f8699bc3ced8278113d4f

Author: generatedunixname1734921407115435

Doc/about.rst

@@ -10,7 +10,7 @@ and now maintained as an independent project.
 .. _reStructuredText: https://docutils.sourceforge.io/rst.html
 .. _Sphinx: https://www.sphinx-doc.org/
 
-.. In the online version of these documents, you can submit comments and suggest
+.. In the online version of this documentation, you can submit comments and suggest
    changes directly on the documentation pages.
 
 Development of the documentation and its toolchain is an entirely volunteer

Doc/tools/templates/indexsidebar.html

@@ -1,5 +1,5 @@
 <h3>{% trans %}Download{% endtrans %}</h3>
-<p><a href="{{ pathto('download') }}">{% trans %}Download these documents{% endtrans %}</a></p>
+<p><a href="{{ pathto('download') }}">{% trans %}Download the documentation{% endtrans %}</a></p>
 <h3>{% trans %}Docs by version{% endtrans %}</h3>
 <ul>
   {# _docs_by_version.html is overwritten by build_docs.py for non-EOL versions #}

Doc/tutorial/stdlib.rst

@@ -36,7 +36,7 @@ aids for working with large modules like :mod:`os`::
    <returns an extensive manual page created from the module's docstrings>
 
 For daily file and directory management tasks, the :mod:`shutil` module provides
-a higher level interface that is easier to use::
+a higher-level interface that is easier to use::
 
    >>> import shutil
    >>> shutil.copyfile('data.db', 'archive.db')
@@ -63,7 +63,7 @@ wildcard searches::
 Command-line arguments
 ======================
 
-Common utility scripts often need to process command line arguments. These
+Common utility scripts often need to process command-line arguments. These
 arguments are stored in the :mod:`sys` module's *argv* attribute as a list.  For
 instance, let's take the following :file:`demo.py` file::
 
@@ -77,7 +77,7 @@ line::
    ['demo.py', 'one', 'two', 'three']
 
 The :mod:`argparse` module provides a more sophisticated mechanism to process
-command line arguments.  The following script extracts one or more filenames
+command-line arguments.  The following script extracts one or more filenames
 and an optional number of lines to be displayed::
 
     import argparse