Add @final to many unsubclassable stdlib classes (#6299)

stdlib/os/__init__.pyi

@@ -37,7 +37,7 @@ from typing import (
     overload,
     runtime_checkable,
 )
-from typing_extensions import Literal
+from typing_extensions import Literal, final
 
 from . import path as _path
 
@@ -262,6 +262,7 @@ if sys.platform != "win32":
 TMP_MAX: int  # Undocumented, but used by tempfile
 
 # ----- os classes (structures) -----
+@final
 class stat_result:
     # For backward compatibility, the return value of stat() is also
     # accessible as a tuple of at least 10 integers giving the most important
@@ -314,6 +315,7 @@ class PathLike(Protocol[_AnyStr_co]):
 
 _FdOrAnyPath = Union[int, StrOrBytesPath]
 
+@final
 class DirEntry(Generic[AnyStr]):
     # This is what the scandir iterator yields
     # The constructor is hidden
@@ -334,6 +336,7 @@ if sys.platform != "win32":
     _Tuple11Int = Tuple[int, int, int, int, int, int, int, int, int, int, int]
     if sys.version_info >= (3, 7):
         # f_fsid was added in https://github.com/python/cpython/pull/4571
+        @final
         class statvfs_result(_Tuple10Int):  # Unix only
             def __new__(cls, seq: _Tuple10Int | _Tuple11Int, dict: dict[str, int] = ...) -> statvfs_result: ...
             n_fields: int
@@ -566,6 +569,7 @@ if sys.platform != "win32":
     def readv(__fd: int, __buffers: Sequence[bytearray]) -> int: ...
     def writev(__fd: int, __buffers: Sequence[bytes]) -> int: ...
 
+@final
 class terminal_size(Tuple[int, int]):
     columns: int
     lines: int