@contextlib.contextmanager
def http_server(app=None, handler_class=WSGIRequestHandler,
            server_class=WSGIServer, bind=('localhost', 8082)):

    server = server_class(bind, handler_class)
    thread = threading.Thread(
        target=server.serve_forever, name='sa-media test server.', daemon=True
    )
     thread.start()
     url = f'http://{server.server_address[0]}:{server.server_address[1]}'
     yield server, url
     server.shutdown()
     thread.join()

File "/usr/local/lib/python3.6/socketserver.py", line 453, in __init__
self.server_bind()
  File "/usr/local/lib/python3.6/wsgiref/simple_server.py", line 50, in server_bind
HTTPServer.server_bind(self)
  File "/usr/local/lib/python3.6/http/server.py", line 136, in server_bind
socketserver.TCPServer.server_bind(self)
  File "/usr/local/lib/python3.6/socketserver.py", line 467, in server_bind
self.socket.bind(self.server_address)
  socket.gaierror: [Errno -2] Name or service not known