update ctypes.CField

Author: guoci

stdlib/_ctypes.pyi

@@ -195,12 +195,18 @@ class CFuncPtr(_PointerLike, _CData, metaclass=_PyCFuncPtrType):
 _GetT = TypeVar("_GetT")
 _SetT = TypeVar("_SetT")
 
-# This class is not exposed. It calls itself _ctypes.CField.
 @final
-@type_check_only
 class _CField(Generic[_CT, _GetT, _SetT]):
+    name: str
+    type: type[_CT]
     offset: int
+    byte_offset: int
+    byte_size: int
     size: int
+    is_bitfield: bool
+    bit_offset: int
+    bit_size: int
+    is_anonymous: bool
     if sys.version_info >= (3, 10):
         @overload
         def __get__(self, instance: None, owner: type[Any] | None = None, /) -> Self: ...

stdlib/ctypes/__init__.pyi

@@ -10,7 +10,7 @@ from _ctypes import (
     _CArgObject as _CArgObject,
     _CData as _CData,
     _CDataType as _CDataType,
-    _CField as _CField,
+    _CField as CField,
     _CTypeBaseType,
     _Pointer as _Pointer,
     _PointerLike as _PointerLike,