add missing type hints for __class_getitem__

stdlib/fileinput.pyi

@@ -2,6 +2,9 @@ import sys
 from _typeshed import Self, StrOrBytesPath
 from typing import IO, Any, AnyStr, Callable, Generic, Iterable, Iterator, Union
 
+if sys.version_info >= (3, 9):
+    from types import GenericAlias
+
 if sys.version_info >= (3, 10):
     def input(
         files: Union[StrOrBytesPath, Iterable[StrOrBytesPath], None] = ...,
@@ -91,6 +94,8 @@ class FileInput(Iterable[AnyStr], Generic[AnyStr]):
     def fileno(self) -> int: ...
     def isfirstline(self) -> bool: ...
     def isstdin(self) -> bool: ...
+    if sys.version_info >= (3, 9):
+        def __class_getitem__(cls, item: Any) -> GenericAlias: ...
 
 if sys.version_info >= (3, 10):
     def hook_compressed(

stdlib/http/cookies.pyi

@@ -1,6 +1,9 @@
 import sys
 from typing import Any, Dict, Generic, Iterable, List, Mapping, Optional, Tuple, TypeVar, Union, overload
 
+if sys.version_info >= (3, 9):
+    from types import GenericAlias
+
 _DataType = Union[str, Mapping[str, Union[str, Morsel[Any]]]]
 _T = TypeVar("_T")
 
@@ -34,6 +37,8 @@ class Morsel(Dict[str, Any], Generic[_T]):
     def output(self, attrs: Optional[List[str]] = ..., header: str = ...) -> str: ...
     def js_output(self, attrs: Optional[List[str]] = ...) -> str: ...
     def OutputString(self, attrs: Optional[List[str]] = ...) -> str: ...
+    if sys.version_info >= (3, 9):
+        def __class_getitem__(cls, item: Any) -> GenericAlias: ...
 
 class BaseCookie(Dict[str, Morsel[_T]], Generic[_T]):
     def __init__(self, input: Optional[_DataType] = ...) -> None: ...

stdlib/os/__init__.pyi

@@ -311,6 +311,8 @@ class stat_result:
 @runtime_checkable
 class PathLike(Protocol[_AnyStr_co]):
     def __fspath__(self) -> _AnyStr_co: ...
+    if sys.version_info >= (3, 9):
+        def __class_getitem__(cls, item: Any) -> GenericAlias: ...
 
 _FdOrAnyPath = Union[int, StrOrBytesPath]
 

stdlib/tempfile.pyi

@@ -205,6 +205,10 @@ class _TemporaryFileWrapper(Generic[AnyStr], IO[AnyStr]):
 # It does not actually derive from IO[AnyStr], but it does implement the
 # protocol.
 class SpooledTemporaryFile(IO[AnyStr]):
+    @property
+    def encoding(self) -> str: ...  # undocumented
+    @property
+    def newlines(self) -> str | Tuple[str, ...] | None: ...  # undocumented
     # bytes needs to go first, as default mode is to open as bytes
     if sys.version_info >= (3, 8):
         @overload
@@ -314,6 +318,8 @@ class SpooledTemporaryFile(IO[AnyStr]):
     def seekable(self) -> bool: ...
     def writable(self) -> bool: ...
     def __next__(self) -> AnyStr: ...
+    if sys.version_info >= (3, 9):
+        def __class_getitem__(cls, item: Any) -> GenericAlias: ...
 
 class TemporaryDirectory(Generic[AnyStr]):
     name: AnyStr