def METHOD_NAME(self):
    client = AsyncClient(incoming_heartbeat=200, outgoing_heartbeat=100)
    client.handle_connect()
    req_frame = client.pop_message()
    self.assertEqual(req_frame.command, Command.CONNECT)
    self.assertEqual(req_frame.headers[Headers.ACCEPT_VERSION], '1.2')
    self.assertEqual(req_frame.headers[Headers.HEARTBEAT], '120,160')