flake8: Enable F811 (#4158)

stdlib/2and3/builtins.pyi

@@ -52,7 +52,7 @@ class object:
     @property
     def __class__(self: _T) -> Type[_T]: ...
     @__class__.setter
-    def __class__(self, __type: Type[object]) -> None: ...
+    def __class__(self, __type: Type[object]) -> None: ...  # noqa: F811
     def __init__(self) -> None: ...
     def __new__(cls) -> Any: ...
     def __setattr__(self, name: str, value: Any) -> None: ...
@@ -1503,7 +1503,7 @@ else:
     def pow(__base: _SupportsPow3[_E, _M, _T_co], __exp: _E, __mod: _M) -> _T_co: ...
 def quit(code: object = ...) -> NoReturn: ...
 if sys.version_info < (3,):
-    def range(__x: int, __y: int = ..., __step: int = ...) -> List[int]: ...
+    def range(__x: int, __y: int = ..., __step: int = ...) -> List[int]: ...  # noqa: F811
     def raw_input(__prompt: Any = ...) -> str: ...
     @overload
     def reduce(__function: Callable[[_T, _S], _T], __iterable: Iterable[_S], __initializer: _T) -> _T: ...

stdlib/2and3/distutils/dist.pyi

@@ -1,7 +1,7 @@
 # Stubs for distutils.dist
 from distutils.cmd import Command
 
-from typing import Any, Dict, Mapping, Optional, Dict, Tuple, Iterable, Text, Type
+from typing import Any, Dict, Iterable, Mapping, Optional, Text, Tuple, Type
 
 
 class Distribution:

stdlib/2and3/hmac.pyi

@@ -1,6 +1,6 @@
 # Stubs for hmac
 
-from typing import Any, Callable, Optional, Union, overload, AnyStr, overload
+from typing import Any, AnyStr, Callable, Optional, Union, overload
 from types import ModuleType
 import sys