The test program should try to connect to a bluetooth device, using asyncio.
The bluetooth address is obviously made up, so it would likely fail to do so, but it should not raise an exception before even trying:

$ python3.5 test_async_btsock.py 
Traceback (most recent call last):
  File "test_async_btsock.py", line 9, in <module>
    loop.run_until_complete(coro)
  File "/usr/lib/python3.5/asyncio/base_events.py", line 373, in run_until_complete
    return future.result()
  File "/usr/lib/python3.5/asyncio/futures.py", line 274, in result
    raise self._exception
  File "/usr/lib/python3.5/asyncio/selector_events.py", line 400, in sock_connect
    base_events._check_resolved_address(sock, address)
  File "/usr/lib/python3.5/asyncio/base_events.py", line 151, in _check_resolved_address
    " got host %r" % host)
ValueError: address must be resolved (IP address), got host '00:01:02:03:04:05'