bpo-33562: Check the global asyncio event loop policy isn't set after any tests (GH-7328)

Lib/test/test_asyncio/test_buffered_proto.py

@@ -4,6 +4,10 @@ import unittest
 from test.test_asyncio import functional as func_tests
 
 
+def tearDownModule():
+    asyncio.set_event_loop_policy(None)
+
+
 class ReceiveStuffProto(asyncio.BufferedProtocol):
     def __init__(self, cb, con_lost_fut):
         self.cb = cb