gh-132983: Add What's New entry for PEP 784 implementation (#133495)

Co-authored-by: Hugo van Kemenade <[email protected]>

Author: emmatyping

Doc/whatsnew/3.14.rst

@@ -71,6 +71,7 @@ Summary -- release highlights
 * :ref:`PEP 761: Discontinuation of PGP signatures <whatsnew314-pep761>`
 * :ref:`PEP 765: Disallow return/break/continue that exit a finally block <whatsnew314-pep765>`
 * :ref:`PEP 768: Safe external debugger interface for CPython <whatsnew314-pep768>`
+* :ref:`PEP 784: Adding Zstandard to the standard library <whatsnew314-pep784>`
 * :ref:`A new type of interpreter <whatsnew314-tail-call>`
 * :ref:`Syntax highlighting in PyREPL <whatsnew314-pyrepl-highlighting>`,
   and color output in :ref:`unittest <whatsnew314-color-unittest>`,
@@ -232,6 +233,51 @@ See :pep:`768` for more details.
 
 (Contributed by Pablo Galindo Salgado, Matt Wozniski, and Ivona Stojanovic in :gh:`131591`.)
 
+.. _whatsnew314-pep784:
+
+PEP 784: Adding Zstandard to the standard library
+-------------------------------------------------
+
+The new ``compression`` package contains modules :mod:`!compression.lzma`,
+:mod:`!compression.bz2`, :mod:`!compression.gzip` and :mod:`!compression.zlib`
+which re-export the :mod:`lzma`, :mod:`bz2`, :mod:`gzip` and :mod:`zlib`
+modules respectively. The new import names under ``compression`` are the
+canonical names for importing these compression modules going forward. However,
+the existing modules names have not been deprecated. Any deprecation or removal
+of the existing compression modules will occur no sooner than five years after
+the release of 3.14.
+
+The new :mod:`!compression.zstd` module provides compression and decompression
+APIs for the Zstandard format via bindings to `Meta's zstd library
+<https://facebook.github.io/zstd/>`__. Zstandard is a widely adopted, highly
+efficient, and fast compression format. In addition to the APIs introduced in
+:mod:`!compression.zstd`, support for reading and writing Zstandard compressed
+archives has been added to the :mod:`tarfile`, :mod:`zipfile`, and
+:mod:`shutil` modules.
+
+Here's an example of using the new module to compress some data:
+
+.. code-block:: python
+
+    from compression import zstd
+    import math
+
+    data = str(math.pi).encode() * 20
+
+    compressed = zstd.compress(data)
+
+    ratio = len(compressed) / len(data)
+    print(f"Achieved compression ratio of {ratio}")
+
+As can be seen, the API is similar to the APIs of the :mod:`!lzma` and
+:mod:`!bz2` modules.
+
+(Contributed by Emma Harper Smith, Adam Turner, Gregory P. Smith, Tomas Roun,
+Victor Stinner, and Rogdham in :gh:`132983`)
+
+.. seealso::
+   :pep:`768`.
+
 
 .. _whatsnew314-remote-pdb:
 
@@ -907,7 +953,7 @@ ast
   (Contributed by Irit Katriel in :gh:`123958`.)
 
 * The ``repr()`` output for AST nodes now includes more information.
-  (Contributed by Tomas R in :gh:`116022`.)
+  (Contributed by Tomas Roun in :gh:`116022`.)
 
 * :func:`ast.parse`, when called with an AST as input, now always verifies
   that the root node type is appropriate.