fixed mypy

src/pwo/notification.py

@@ -25,12 +25,12 @@ class Subscriber:
 
     async def wait(self, tout: Optional[float]) -> bool:
 
-        future = self._loop.create_future()
+        future: Future[bool] = self._loop.create_future()
         self._event = future
         try:
             async with timeout(tout):
                 log.debug('Subscriber %s is waiting for an event', id(self))
-                await future
+                return await future
         except TimeoutError:
             return False