Added __class_getitem__ (#4695)

Resolves #4682

Co-authored-by: hauntsaninja <>

stdlib/3/multiprocessing/managers.pyi

@@ -30,6 +30,9 @@ if sys.version_info >= (3, 8):
     _SharedMemory = SharedMemory
     _ShareableList = ShareableList
 
+if sys.version_info >= (3, 9):
+    from types import GenericAlias
+
 _T = TypeVar("_T")
 _KT = TypeVar("_KT")
 _VT = TypeVar("_VT")
@@ -89,6 +92,8 @@ class ValueProxy(BaseProxy, Generic[_T]):
     def get(self) -> _T: ...
     def set(self, value: _T) -> None: ...
     value: _T
+    if sys.version_info >= (3, 9):
+        def __class_getitem__(cls, item: Any) -> GenericAlias: ...
 
 # Returned by BaseManager.get_server()
 class Server:

stdlib/3/multiprocessing/pool.pyi

@@ -1,5 +1,9 @@
+import sys
 from typing import Any, Callable, ContextManager, Generic, Iterable, Iterator, List, Mapping, Optional, TypeVar
 
+if sys.version_info >= (3, 9):
+    from types import GenericAlias
+
 _PT = TypeVar("_PT", bound=Pool)
 _S = TypeVar("_S")
 _T = TypeVar("_T")
@@ -9,6 +13,8 @@ class ApplyResult(Generic[_T]):
     def wait(self, timeout: Optional[float] = ...) -> None: ...
     def ready(self) -> bool: ...
     def successful(self) -> bool: ...
+    if sys.version_info >= (3, 9):
+        def __class_getitem__(cls, item: Any) -> GenericAlias: ...
 
 # alias created during issue #17805
 AsyncResult = ApplyResult

stdlib/3/multiprocessing/queues.pyi

@@ -1,6 +1,10 @@
 import queue
+import sys
 from typing import Any, Generic, Optional, TypeVar
 
+if sys.version_info >= (3, 9):
+    from types import GenericAlias
+
 _T = TypeVar("_T")
 
 class Queue(queue.Queue[_T]):
@@ -27,3 +31,5 @@ class SimpleQueue(Generic[_T]):
     def empty(self) -> bool: ...
     def get(self) -> _T: ...
     def put(self, item: _T) -> None: ...
+    if sys.version_info >= (3, 9):
+        def __class_getitem__(cls, item: Any) -> GenericAlias: ...

stdlib/3/multiprocessing/shared_memory.pyi

@@ -1,5 +1,8 @@
 import sys
-from typing import Generic, Iterable, Optional, Tuple, TypeVar
+from typing import Any, Generic, Iterable, Optional, Tuple, TypeVar
+
+if sys.version_info >= (3, 9):
+    from types import GenericAlias
 
 _S = TypeVar("_S")
 _SLT = TypeVar("_SLT", int, float, bool, str, bytes, None)
@@ -26,3 +29,5 @@ if sys.version_info >= (3, 8):
         def format(self) -> str: ...
         def count(self, value: _SLT) -> int: ...
         def index(self, value: _SLT) -> int: ...
+        if sys.version_info >= (3, 9):
+            def __class_getitem__(cls, item: Any) -> GenericAlias: ...