From 06e9a35169e125488d4ae9228626eb95375f3a14 Mon Sep 17 00:00:00 2001
From: "Miss Islington (bot)"
 <31488909+miss-islington@users.noreply.github.com>
Date: Wed, 25 Aug 2021 11:36:47 -0700
Subject: bpo-44524: Don't modify MRO when inheriting from typing.Annotated
 (GH-27841)

(cherry picked from commit 23384a1749359f0ae7aaae052073d44b59e715a1)

Co-authored-by: Ken Jin <28750310+Fidget-Spinner@users.noreply.github.com>
---
 Lib/test/test_typing.py | 5 +++++
 Lib/typing.py           | 7 ++++++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/Lib/test/test_typing.py b/Lib/test/test_typing.py
index b1cd547..7b2fd69 100644
--- a/Lib/test/test_typing.py
+++ b/Lib/test/test_typing.py
@@ -4512,6 +4512,11 @@ class AnnotatedTests(BaseTestCase):
         X = List[Annotated[T, 5]]
         self.assertEqual(X[int], List[Annotated[int, 5]])
 
+    def test_annotated_mro(self):
+        class X(Annotated[int, (1, 10)]): ...
+        self.assertEqual(X.__mro__, (X, int, object),
+                         "Annotated should be transparent.")
+
 
 class TypeAliasTests(BaseTestCase):
     def test_canonical_usage_with_variable_annotation(self):
diff --git a/Lib/typing.py b/Lib/typing.py
index 4935460..423329a 100644
--- a/Lib/typing.py
+++ b/Lib/typing.py
@@ -1573,7 +1573,7 @@ class _AnnotatedAlias(_GenericAlias, _root=True):
         if isinstance(origin, _AnnotatedAlias):
             metadata = origin.__metadata__ + metadata
             origin = origin.__origin__
-        super().__init__(origin, origin, name="Annotated")
+        super().__init__(origin, origin)
         self.__metadata__ = metadata
 
     def copy_with(self, params):
@@ -1601,6 +1601,11 @@ class _AnnotatedAlias(_GenericAlias, _root=True):
     def __hash__(self):
         return hash((self.__origin__, self.__metadata__))
 
+    def __getattr__(self, attr):
+        if attr in {'__name__', '__qualname__'}:
+            return 'Annotated'
+        return super().__getattr__(attr)
+
 
 class Annotated:
     """Add context specific metadata to a type.
-- 
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