bpo-35864: Replace OrderedDict with regular dict in namedtuple() (#11708)

* Change from OrderedDict to a regular dict

* Add blurb
diff --git a/Doc/library/collections.rst b/Doc/library/collections.rst
index bfbf8a7..3fa8b32 100644
--- a/Doc/library/collections.rst
+++ b/Doc/library/collections.rst
@@ -894,11 +894,18 @@
 
         >>> p = Point(x=11, y=22)
         >>> p._asdict()
-        OrderedDict([('x', 11), ('y', 22)])
+        {'x': 11, 'y': 22}
 
     .. versionchanged:: 3.1
         Returns an :class:`OrderedDict` instead of a regular :class:`dict`.
 
+    .. versionchanged:: 3.8
+        Returns a regular :class:`dict` instead of an :class:`OrderedDict`.
+        As of Python 3.7, regular dicts are guaranteed to be ordered.  If the
+        extra features of :class:`OrderedDict` are required, the suggested
+        remediation is to cast the result to the desired type:
+        ``OrderedDict(nt._asdict())``.
+
 .. method:: somenamedtuple._replace(**kwargs)
 
     Return a new instance of the named tuple replacing specified fields with new