[3.9] bpo-41370: Add note about ForwardRefs and PEP585 generic types in docs (GH-25183) (GH-25184)

(cherry picked from commit 2b5913b)


Co-authored-by: Ken Jin <[email protected]>

Automerge-Triggered-By: GH:gvanrossum

Author: miss-islington

Doc/library/typing.rst

@@ -1710,10 +1710,15 @@ Introspection helpers
 .. class:: ForwardRef
 
    A class used for internal typing representation of string forward references.
-   For example, ``list["SomeClass"]`` is implicitly transformed into
-   ``list[ForwardRef("SomeClass")]``.  This class should not be instantiated by
+   For example, ``List["SomeClass"]`` is implicitly transformed into
+   ``List[ForwardRef("SomeClass")]``.  This class should not be instantiated by
    a user, but may be used by introspection tools.
 
+   .. note::
+      :pep:`585` generic types such as ``list["SomeClass"]`` will not be
+      implicitly transformed into ``list[ForwardRef("SomeClass")]`` and thus
+      will not automatically resolve to ``list[SomeClass]``.
+
    .. versionadded:: 3.7.4
 
 Constant