Remove some pytype workarounds from stdlib (#14470)

Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

stdlib/asyncio/base_futures.pyi

@@ -1,19 +1,17 @@
+from _asyncio import Future
 from collections.abc import Callable, Sequence
 from contextvars import Context
 from typing import Any, Final
+from typing_extensions import TypeIs
 
 from . import futures
 
 __all__ = ()
 
-# asyncio defines 'isfuture()' in base_futures.py and re-imports it in futures.py
-# but it leads to circular import error in pytype tool.
-# That's why the import order is reversed.
-from .futures import isfuture as isfuture
-
 _PENDING: Final = "PENDING"  # undocumented
 _CANCELLED: Final = "CANCELLED"  # undocumented
 _FINISHED: Final = "FINISHED"  # undocumented
 
+def isfuture(obj: object) -> TypeIs[Future[Any]]: ...
 def _format_callbacks(cb: Sequence[tuple[Callable[[futures.Future[Any]], None], Context]]) -> str: ...  # undocumented
 def _future_repr_info(future: futures.Future[Any]) -> list[str]: ...  # undocumented

stdlib/asyncio/futures.pyi

@@ -1,9 +1,9 @@
 import sys
 from _asyncio import Future as Future
 from concurrent.futures._base import Future as _ConcurrentFuture
-from typing import Any, TypeVar
-from typing_extensions import TypeIs
+from typing import TypeVar
 
+from .base_futures import isfuture as isfuture
 from .events import AbstractEventLoop
 
 # Keep asyncio.__all__ updated with any changes to __all__ here
@@ -16,8 +16,4 @@ else:
 
 _T = TypeVar("_T")
 
-# asyncio defines 'isfuture()' in base_futures.py and re-imports it in futures.py
-# but it leads to circular import error in pytype tool.
-# That's why the import order is reversed.
-def isfuture(obj: object) -> TypeIs[Future[Any]]: ...
 def wrap_future(future: _ConcurrentFuture[_T] | Future[_T], *, loop: AbstractEventLoop | None = None) -> Future[_T]: ...