gh-133951: Add venv changes to documentation and whatsnew (GH-139704)

Author: Cycloctane

Doc/library/venv.rst

@@ -407,6 +407,8 @@ creation according to their needs, the :class:`EnvBuilder` class.
 
         * ``lib_path`` - The purelib path for the virtual environment.
 
+        * ``platlib_path`` - The platlib path for the virtual environment.
+
         * ``bin_path`` - The script path for the virtual environment.
 
         * ``bin_name`` - The name of the script path relative to the virtual
@@ -431,6 +433,9 @@ creation according to their needs, the :class:`EnvBuilder` class.
            The attribute ``lib_path`` was added to the context, and the context
            object was documented.
 
+        .. versionchanged:: 3.15
+           The attribute ``platlib_path`` was added to the context.
+
     .. method:: create_configuration(context)
 
         Creates the ``pyvenv.cfg`` configuration file in the environment.

Doc/whatsnew/3.15.rst

@@ -601,6 +601,17 @@ unittest
   (Contributed by Garry Cairns in :gh:`134567`.)
 
 
+venv
+----
+
+* On POSIX platforms, platlib directories will be created if needed when
+  creating virtual environments, instead of using ``lib64 -> lib`` symlink.
+  This means purelib and platlib of virtual environments no longer share the
+  same ``lib`` directory on platforms where :data:`sys.platlibdir` is not
+  equal to ``lib``.
+  (Contributed by Rui Xi in :gh:`133951`.)
+
+
 xml.parsers.expat
 -----------------