From 79801e9cf1e645e0df6673277cad29362cd1fd5f Mon Sep 17 00:00:00 2001
From: efahl <36704995+efahl@users.noreply.github.com>
Date: Mon, 12 Apr 2021 05:54:12 +0000
Subject: [PATCH 1/3] bpo-41515: fix KeyError raised in get_type_hints

typing.get_type_hints raises KeyError on synthetic modules that don't appear in sys.modules.
---
 Lib/test/test_typing.py | 6 ++++++
 Lib/typing.py           | 5 ++++-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/Lib/test/test_typing.py b/Lib/test/test_typing.py
index 82c517a4e600248..1ab3bd248e25cc8 100644
--- a/Lib/test/test_typing.py
+++ b/Lib/test/test_typing.py
@@ -2267,6 +2267,12 @@ def test_no_isinstance(self):
         with self.assertRaises(TypeError):
             issubclass(int, ClassVar)
 
+    def test_bad_module(self):
+        # bpo-41515
+        class BadModule:
+            pass
+        BadModule.__module__ = 'bad' # Something not in sys.modules
+        assert(get_type_hints(BadModule), {})
 
 class FinalTests(BaseTestCase):
 
diff --git a/Lib/typing.py b/Lib/typing.py
index a24c01f0e3b9e36..d9a76d2bb465258 100644
--- a/Lib/typing.py
+++ b/Lib/typing.py
@@ -1628,7 +1628,10 @@ def get_type_hints(obj, globalns=None, localns=None, include_extras=False):
         hints = {}
         for base in reversed(obj.__mro__):
             if globalns is None:
-                base_globals = sys.modules[base.__module__].__dict__
+                try:
+                    base_globals = sys.modules[base.__module__].__dict__
+                except KeyError:
+                    continue
             else:
                 base_globals = globalns
             ann = base.__dict__.get('__annotations__', {})

From abca784740d336fbdaa802027d1216f7badc3d99 Mon Sep 17 00:00:00 2001
From: efahl <36704995+efahl@users.noreply.github.com>
Date: Mon, 12 Apr 2021 06:01:25 +0000
Subject: [PATCH 2/3] Add news entry.

---
 .../next/Library/2021-04-12-06-01-10.bpo-41515.YaVReb.rst       | 2 ++
 1 file changed, 2 insertions(+)
 create mode 100644 Misc/NEWS.d/next/Library/2021-04-12-06-01-10.bpo-41515.YaVReb.rst

diff --git a/Misc/NEWS.d/next/Library/2021-04-12-06-01-10.bpo-41515.YaVReb.rst b/Misc/NEWS.d/next/Library/2021-04-12-06-01-10.bpo-41515.YaVReb.rst
new file mode 100644
index 000000000000000..b695f14909f5cee
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2021-04-12-06-01-10.bpo-41515.YaVReb.rst
@@ -0,0 +1,2 @@
+Fix :exc:`KeyError` raised in :func:`typing.get_type_hints()` due to
+synthetic modules that don't appear in ``sys.modules``.

From 3623477637cdaef000555d0067e5d78ab857acf2 Mon Sep 17 00:00:00 2001
From: Guido van Rossum <gvanrossum@gmail.com>
Date: Mon, 12 Apr 2021 10:18:13 -0700
Subject: [PATCH 3/3] Fix markup in news item

Co-authored-by: Ken Jin <28750310+Fidget-Spinner@users.noreply.github.com>
---
 .../next/Library/2021-04-12-06-01-10.bpo-41515.YaVReb.rst       | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Misc/NEWS.d/next/Library/2021-04-12-06-01-10.bpo-41515.YaVReb.rst b/Misc/NEWS.d/next/Library/2021-04-12-06-01-10.bpo-41515.YaVReb.rst
index b695f14909f5cee..aef5c1791dfeac4 100644
--- a/Misc/NEWS.d/next/Library/2021-04-12-06-01-10.bpo-41515.YaVReb.rst
+++ b/Misc/NEWS.d/next/Library/2021-04-12-06-01-10.bpo-41515.YaVReb.rst
@@ -1,2 +1,2 @@
-Fix :exc:`KeyError` raised in :func:`typing.get_type_hints()` due to
+Fix :exc:`KeyError` raised in :func:`typing.get_type_hints` due to
 synthetic modules that don't appear in ``sys.modules``.