Issue #21645: test_asyncio, log debug trace into sys.__stderr__, not in

sys.stderr, to get output even if tests are run with the -j command line
option.

Lib/test/test_asyncio/test_streams.py

@@ -615,7 +615,7 @@ os.close(fd)
         logger = logging.getLogger('asyncio')
         log_level = logger.level
         try:
-            log_handler = logging.StreamHandler(sys.stderr)
+            log_handler = logging.StreamHandler(sys.__stderr__)
             logger.addHandler(log_handler)
             logger.setLevel(logging.DEBUG)
             # FIXME: Debug code for issue #21645 ---