Move What's New entry to correct section, add credits

python · ncoghlan · May 21, 2024 · May 20, 2024 · May 20, 2024 · May 20, 2024
commit a87f1d73a28198845f7512269b3388ffa988d669
diff --git a/Doc/whatsnew/3.13.rst b/Doc/whatsnew/3.13.rst
@@ -247,6 +247,33 @@ Improved Error Messages
   through ``self.X`` from any function in its body. (Contributed by Irit Katriel
   in :gh:`115775`.)
 
+
+Defined mutation semantics for ``locals()``
+-------------------------------------------
+
+Historically, the semantics for mutating the return value of :func:`locals` have
+been left to individual Python implementations to define.
+
+Through :pep:`667`, Python 3.13 standardises the historical behaviour of CPython
+for most code execution scopes, but changes
+:term:`optimised scopes <optimised scope>` (functions, generators, coroutines,
+comprehensions, and generator expressions) to explicitly return independent
+snapshots of the currently assigned local variables, including locally
+referenced nonlocal variables captured in closures.
+
+To ensure debuggers and similar tools can reliably update local variables in
+scopes affected by this change, :attr:`FrameType.f_locals <frame.f_locals>` now
+returns a write-through proxy to the frame's local and locally referenced
+nonlocal variables in these scopes, rather than returning an inconsistently
+updated shared  ``dict`` instance with undefined runtime semantics.
+
+See :pep:`667` for more details, including related C API changes and
+deprecations.
+
+(PEP and implementation contributed by Mark Shannon and Tian Gao in
+:gh:`74929`. Documentation updates provided by Guido van Rossum and
+Alyssa Coghlan.)
+
 Incremental Garbage Collection
 ------------------------------
 
@@ -371,29 +398,6 @@ pip 24.1b1 or newer is required to install packages with C extensions in the
 free-threaded build.
 
 
-Defined mutation semantics for ``locals()``
--------------------------------------------
-
-Historically, the semantics for mutating the return value of :func:`locals` have
-been left to individual Python implementations to define.
-
-Through :pep:`667`, Python 3.13 standardises the historical behaviour of CPython
-for most code execution scopes, but changes
-:term:`optimised scopes <optimised scope>` (functions, generators, coroutines,
-comprehensions, and generator expressions) to explicitly return independent
-snapshots of the currently assigned local variables, including locally
-referenced nonlocal variables captured in closures.
-
-To ensure debuggers and similar tools can reliably update local variables in
-scopes affected by this change, :attr:`FrameType.f_locals <frame.f_locals>` now
-returns a write-through proxy to the frame's local and locally referenced
-nonlocal variables in these scopes, rather than returning an inconsistently
-updated shared  ``dict`` instance with undefined runtime semantics.
-
-See :pep:`667` for more details, including related C API changes and
-deprecations.
-
-
 Other Language Changes
 ======================