Drop needless if check

tractor/_actor.py

@@ -282,9 +282,7 @@ class Actor:
                 if msg is None:  # terminate sentinel
                     log.debug(
                         f"Cancelling all tasks for {chan} from {chan.uid}")
-                    scopes = self._rpc_tasks.pop(chan, None)
+                    for scope, func in self._rpc_tasks.pop(chan, ()):
-                    if scopes:
-                        for scope, func in scopes:
                         scope.cancel()
 
                     log.debug(