gh-84559: gh-103134: Whats new 3.14 entries for multiprocessing. (GH-…

…126697)

Doc/whatsnew/3.14.rst

@@ -250,6 +250,12 @@ concurrent.futures
   same process) to Python code.  This is separate from the proposed API
   in :pep:`734`.
   (Contributed by Eric Snow in :gh:`124548`.)
+* The default ``ProcessPoolExecutor`` start method (see
+  :ref:`multiprocessing-start-methods`) changed from *fork* to *forkserver* on
+  platforms other than macOS & Windows. If you require the threading
+  incompatible *fork* start method you must explicitly request it by
+  supplying a *mp_context* to :class:`concurrent.futures.ProcessPoolExecutor`.
+  (Contributed by Gregory P.  Smith in :gh:`84559`.)
 
 ctypes
 ------
@@ -357,6 +363,25 @@ json
   (Contributed by Trey Hunner in :gh:`122873`.)
 
 
+multiprocessing
+---------------
+
+* The default start method (see :ref:`multiprocessing-start-methods`) changed
+  from *fork* to *forkserver* on platforms other than macOS & Windows where
+  it was already *spawn*. If you require the threading incompatible *fork*
+  start method you must explicitly request it using a context from
+  :func:`multiprocessing.get_context` (preferred) or change the default via
+  :func:`multiprocessing.set_start_method`.
+  (Contributed by Gregory P. Smith in :gh:`84559`.)
+* The :ref:`multiprocessing proxy objects <multiprocessing-proxy_objects>`
+  for *list* and *dict* types gain previously overlooked missing methods:
+
+   * :meth:`!clear` and :meth:`!copy` for proxies of :class:`list`.
+   * :meth:`~dict.fromkeys`, ``reversed(d)``, ``d | {}``, ``{} | d``,
+     ``d |= {'b': 2}`` for proxies of :class:`dict`.
+
+  (Contributed by Roy Hyunjin Han for :gh:`103134`)
+
 operator
 --------
 
@@ -511,14 +536,6 @@ Deprecated
   as a single positional argument.
   (Contributed by Serhiy Storchaka in :gh:`109218`.)
 
-* :mod:`multiprocessing` and :mod:`concurrent.futures`:
-  The default start method (see :ref:`multiprocessing-start-methods`) changed
-  away from *fork* to *forkserver* on platforms where it was not already
-  *spawn* (Windows & macOS). If you require the threading incompatible *fork*
-  start method you must explicitly specify it when using :mod:`multiprocessing`
-  or :mod:`concurrent.futures` APIs.
-  (Contributed by Gregory P. Smith in :gh:`84559`.)
-
 * :mod:`os`:
   :term:`Soft deprecate <soft deprecated>` :func:`os.popen` and
   :func:`os.spawn* <os.spawnl>` functions. They should no longer be used to