From 7df48a8b066bf1be0f363570925d14740bd5ba8f Mon Sep 17 00:00:00 2001
From: Joshua Bronson <jabronson@gmail.com>
Date: Sat, 10 Dec 2022 11:47:14 -0500
Subject: [PATCH 1/5] Revert "`Collection` is `Sized` (#8977)"

This reverts commit 5bbba5d008ffe6f26ffe4fb9e7c7b3e0765a2b0a.
---
 stdlib/builtins.pyi | 2 +-
 stdlib/typing.pyi   | 5 ++++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/stdlib/builtins.pyi b/stdlib/builtins.pyi
index df74a00a42bc..12b2069c636f 100644
--- a/stdlib/builtins.pyi
+++ b/stdlib/builtins.pyi
@@ -804,7 +804,7 @@ class bytearray(MutableSequence[int], ByteString):
     def __alloc__(self) -> int: ...
 
 @final
-class memoryview(Sequence[int]):
+class memoryview(Sized, Sequence[int]):
     @property
     def format(self) -> str: ...
     @property
diff --git a/stdlib/typing.pyi b/stdlib/typing.pyi
index cc27ae7dbda2..3c577ce15270 100644
--- a/stdlib/typing.pyi
+++ b/stdlib/typing.pyi
@@ -452,7 +452,10 @@ class Container(Protocol[_T_co]):
     def __contains__(self, __x: object) -> bool: ...
 
 @runtime_checkable
-class Collection(Sized, Iterable[_T_co], Container[_T_co], Protocol[_T_co]): ...
+class Collection(Iterable[_T_co], Container[_T_co], Protocol[_T_co]):
+    # Implement Sized (but don't have it as a base class).
+    @abstractmethod
+    def __len__(self) -> int: ...
 
 class Sequence(Collection[_T_co], Reversible[_T_co], Generic[_T_co]):
     @overload

From c9ae4f93739edbeb2dc5ca2b1305ed2c2e500528 Mon Sep 17 00:00:00 2001
From: Joshua Bronson <jabronson@gmail.com>
Date: Sat, 10 Dec 2022 11:47:48 -0500
Subject: [PATCH 2/5] Revert "typing: remove metaclass from Sized (#9058)"

This reverts commit a3ce51209544d64d03018b3927051375f1bebe82.
---
 stdlib/typing.pyi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/stdlib/typing.pyi b/stdlib/typing.pyi
index 3c577ce15270..71018003b6d9 100644
--- a/stdlib/typing.pyi
+++ b/stdlib/typing.pyi
@@ -325,7 +325,7 @@ class SupportsRound(Protocol[_T_co]):
     def __round__(self, __ndigits: int) -> _T_co: ...
 
 @runtime_checkable
-class Sized(Protocol):
+class Sized(Protocol, metaclass=ABCMeta):
     @abstractmethod
     def __len__(self) -> int: ...
 

From 69e36c1b988e54e129402973a6e23c508ed615a2 Mon Sep 17 00:00:00 2001
From: Joshua Bronson <jabronson@gmail.com>
Date: Sat, 10 Dec 2022 11:58:39 -0500
Subject: [PATCH 3/5] Add regression test for issue 9296.

---
 .../typing/check_regression_issue_9296.py      | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)
 create mode 100644 test_cases/stdlib/typing/check_regression_issue_9296.py

diff --git a/test_cases/stdlib/typing/check_regression_issue_9296.py b/test_cases/stdlib/typing/check_regression_issue_9296.py
new file mode 100644
index 000000000000..1ad6311847d8
--- /dev/null
+++ b/test_cases/stdlib/typing/check_regression_issue_9296.py
@@ -0,0 +1,18 @@
+from __future__ import annotations
+
+import typing as t
+
+
+KT = t.TypeVar("KT")
+
+
+class MyKeysView(t.KeysView[KT]):
+    pass
+
+
+d: dict[t.Any, t.Any] = {}
+dict_keys = type(d.keys())
+
+# This should not cause an error like `Member "register" is unknown`:
+MyKeysView.register(dict_keys)
+

From 17a8e5f9523fbf1f451c2e142d9faf952695f82a Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Sat, 10 Dec 2022 17:40:36 +0000
Subject: [PATCH 4/5] [pre-commit.ci] auto fixes from pre-commit.com hooks

---
 test_cases/stdlib/typing/check_regression_issue_9296.py | 2 --
 1 file changed, 2 deletions(-)

diff --git a/test_cases/stdlib/typing/check_regression_issue_9296.py b/test_cases/stdlib/typing/check_regression_issue_9296.py
index 1ad6311847d8..34c5631aeb1a 100644
--- a/test_cases/stdlib/typing/check_regression_issue_9296.py
+++ b/test_cases/stdlib/typing/check_regression_issue_9296.py
@@ -2,7 +2,6 @@
 
 import typing as t
 
-
 KT = t.TypeVar("KT")
 
 
@@ -15,4 +14,3 @@ class MyKeysView(t.KeysView[KT]):
 
 # This should not cause an error like `Member "register" is unknown`:
 MyKeysView.register(dict_keys)
-

From 8a329ba6eb3e393d376c6d1ab62c9a96a805ec68 Mon Sep 17 00:00:00 2001
From: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Date: Sat, 10 Dec 2022 09:56:50 -0800
Subject: [PATCH 5/5] Update stdlib/builtins.pyi

---
 stdlib/builtins.pyi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/stdlib/builtins.pyi b/stdlib/builtins.pyi
index 12b2069c636f..df74a00a42bc 100644
--- a/stdlib/builtins.pyi
+++ b/stdlib/builtins.pyi
@@ -804,7 +804,7 @@ class bytearray(MutableSequence[int], ByteString):
     def __alloc__(self) -> int: ...
 
 @final
-class memoryview(Sized, Sequence[int]):
+class memoryview(Sequence[int]):
     @property
     def format(self) -> str: ...
     @property