diff --git a/stdlib/3/asyncio/events.pyi b/stdlib/3/asyncio/events.pyi
index acfd61031..642de7b7d 100644
--- a/stdlib/3/asyncio/events.pyi
+++ b/stdlib/3/asyncio/events.pyi
@@ -198,7 +198,7 @@ class AbstractEventLoopPolicy(metaclass=ABCMeta):
     @abstractmethod
     def get_event_loop(self) -> AbstractEventLoop: ...
     @abstractmethod
-    def set_event_loop(self, loop: AbstractEventLoop) -> None: ...
+    def set_event_loop(self, loop: Optional[AbstractEventLoop]) -> None: ...
     @abstractmethod
     def new_event_loop(self) -> AbstractEventLoop: ...
     # Child processes handling (Unix only).
@@ -210,14 +210,14 @@ class AbstractEventLoopPolicy(metaclass=ABCMeta):
 class BaseDefaultEventLoopPolicy(AbstractEventLoopPolicy, metaclass=ABCMeta):
     def __init__(self) -> None: ...
     def get_event_loop(self) -> AbstractEventLoop: ...
-    def set_event_loop(self, loop: AbstractEventLoop) -> None: ...
+    def set_event_loop(self, loop: Optional[AbstractEventLoop]) -> None: ...
     def new_event_loop(self) -> AbstractEventLoop: ...
 
 def get_event_loop_policy() -> AbstractEventLoopPolicy: ...
 def set_event_loop_policy(policy: AbstractEventLoopPolicy) -> None: ...
 
 def get_event_loop() -> AbstractEventLoop: ...
-def set_event_loop(loop: AbstractEventLoop) -> None: ...
+def set_event_loop(loop: Optional[AbstractEventLoop]) -> None: ...
 def new_event_loop() -> AbstractEventLoop: ...
 
 def get_child_watcher() -> Any: ...  # TODO: unix_events.AbstractChildWatcher