>python -X tracemalloc=30 -m unittest test.test_asyncio.test_events.ProactorEventLoopTests.test_create_server_ssl_verify_failed
Running Debug|x64 interpreter...
lib\asyncio\sslproto.py:330: ResourceWarning: unclosed transport <asyncio.sslproto._SSLProtocolTransport object at 0x000002501E93DA18>
  source=self)
Object allocated at (most recent call first):
  File "lib\asyncio\sslproto.py", lineno 435
    self, self._app_protocol)
  File "lib\asyncio\proactor_events.py", lineno 401
    server_side, server_hostname)
  File "lib\asyncio\proactor_events.py", lineno 507
    extra={'peername': addr}, server=server)
  File "lib\asyncio\events.py", lineno 122
    self._callback(*self._args)
  File "lib\asyncio\base_events.py", lineno 1413
    handle._run()
  File "lib\asyncio\base_events.py", lineno 420
    self._run_once()
  File "lib\asyncio\base_events.py", lineno 453
    self.run_forever()
  File "lib\test\test_asyncio\test_events.py", lineno 1099
    self.loop.run_until_complete(f_c)
  File "lib\unittest\case.py", lineno 615
    testMethod()
  File "lib\unittest\case.py", lineno 663
    return self.run(*args, **kwds)
  File "lib\unittest\suite.py", lineno 122
    test(result)
  File "lib\unittest\suite.py", lineno 84
    return self.run(*args, **kwds)
  File "lib\unittest\suite.py", lineno 122
    test(result)
  File "lib\unittest\suite.py", lineno 84
    return self.run(*args, **kwds)
  File "lib\unittest\runner.py", lineno 176
    test(result)
  File "lib\unittest\main.py", lineno 256
    self.result = testRunner.run(self.test)
  File "lib\unittest\main.py", lineno 95
    self.runTests()
  File "lib\unittest\__main__.py", lineno 18
    main(module=None)
  File "lib\runpy.py", lineno 85
    exec(code, run_globals)
  File "lib\runpy.py", lineno 193
    "__main__", mod_spec)
.
----------------------------------------------------------------------
Ran 1 test in 1.408s

OK

I don't know how, but this issue has been fixed in the meanwhile.