Revert __eq__ removal (#8487)

Refs #8483

Author: sobolevn

stdlib/_weakrefset.pyi

@@ -39,6 +39,7 @@ class WeakSet(MutableSet[_T], Generic[_T]):
     def issuperset(self, other: Iterable[_T]) -> bool: ...
     def __ge__(self, other: Iterable[_T]) -> bool: ...
     def __gt__(self, other: Iterable[_T]) -> bool: ...
+    def __eq__(self, other: object) -> bool: ...
     def symmetric_difference(self, other: Iterable[_S]) -> WeakSet[_S | _T]: ...
     def __xor__(self, other: Iterable[_S]) -> WeakSet[_S | _T]: ...
     def symmetric_difference_update(self, other: Iterable[_T]) -> None: ...

stdlib/argparse.pyi

@@ -330,6 +330,7 @@ class Namespace(_AttributeHolder):
     def __getattr__(self, name: str) -> Any: ...
     def __setattr__(self, __name: str, __value: Any) -> None: ...
     def __contains__(self, key: str) -> bool: ...
+    def __eq__(self, other: object) -> bool: ...
 
 class FileType:
     # undocumented

stdlib/asyncio/events.pyi

@@ -91,6 +91,7 @@ class TimerHandle(Handle):
     def __le__(self, other: TimerHandle) -> bool: ...
     def __gt__(self, other: TimerHandle) -> bool: ...
     def __ge__(self, other: TimerHandle) -> bool: ...
+    def __eq__(self, other: object) -> bool: ...
 
 class AbstractServer:
     @abstractmethod