asyncio, Tulip issue 171: BaseEventLoop.close() now raises an exception if the

event loop is running. You must first stop the event loop and then wait until
it stopped, before closing it.

Lib/asyncio/proactor_events.py

@@ -355,12 +355,12 @@ class BaseProactorEventLoop(base_events.BaseEventLoop):
     def close(self):
         if self.is_closed():
             return
+        super().close()
         self._stop_accept_futures()
         self._close_self_pipe()
         self._proactor.close()
         self._proactor = None
         self._selector = None
-        super().close()
 
     def sock_recv(self, sock, n):
         return self._proactor.recv(sock, n)