Add overload import

Author: guoci

stdlib/sys/__init__.pyi

@@ -5,7 +5,7 @@ from builtins import object as _object
 from collections.abc import AsyncGenerator, Callable, Sequence
 from io import TextIOWrapper
 from types import FrameType, ModuleType, TracebackType
-from typing import Any, Final, Literal, NoReturn, Protocol, TextIO, TypeVar, final, type_check_only
+from typing import Any, Final, Literal, NoReturn, Protocol, TextIO, TypeVar, final, overload, type_check_only
 from typing_extensions import LiteralString, TypeAlias, deprecated
 
 _T = TypeVar("_T")