pythongh-97966: Update uname docs to clarify the special nature of the platform attribute and to indicate when it became late-bound. (python#97972)

Author: jaraco

Doc/library/platform.rst

@@ -168,16 +168,20 @@ Cross Platform
    containing six attributes: :attr:`system`, :attr:`node`, :attr:`release`,
    :attr:`version`, :attr:`machine`, and :attr:`processor`.
 
-   Note that this adds a sixth attribute (:attr:`processor`) not present
-   in the :func:`os.uname` result.  Also, the attribute names are different
-   for the first two attributes; :func:`os.uname` names them
-   :attr:`sysname` and :attr:`nodename`.
+   :attr:`processor` is resolved late, on demand.
+
+   Note: the first two attribute names differ from the names presented by
+   :func:`os.uname`, where they are named :attr:`sysname` and
+   :attr:`nodename`.
 
    Entries which cannot be determined are set to ``''``.
 
    .. versionchanged:: 3.3
       Result changed from a tuple to a :func:`~collections.namedtuple`.
 
+   .. versionchanged:: 3.9
+      :attr:`processor` is resolved late instead of immediately.
+
 
 Java Platform
 -------------

Misc/NEWS.d/next/Documentation/2022-10-06-13-00-28.gh-issue-97966.fz7kFg.rst

@@ -0,0 +1,2 @@
+Update uname docs to clarify the special nature of the platform attribute
+and to indicate when it became late-bound.