How to get realtime top command output using asyncio.create_subprocess_exec when python code is run as a background service?

I have a python code that runs Linux top command using asyncio.create_subprocess_exec to get the real-time output and send it to a WebSocket connection.

The code works well when I run it in the bash shell, but it doesn't work when I run the code as a background service.

I get this error in the logs b'Error opening terminal: unknown.\r\n'.

I suspect that the backend service is not able to execute the Linux top command in the terminal.

My Question is

How do I make the background service access the tty (terminal) to execute the top command and read its output?

I am using python3.6, Asyncio, and aiohttp libraries.

code snippet

async def execute_top(self,request):
       cmd = ['top']
       line_count = 0
       ws = request.pop('ws')
       try:
         async for res in self.run_commands(cmd):
                await ws.send_str(res)
       except Exception as e:
             self.log.error("{}".format(e))
 
async def run_commands(self,command):
    master, slave = pty.openpty()
    self.log.info("tty status : {}".format(sys.stdout.isatty()))
    process = await asyncio.create_subprocess_exec(*command, stdout=slave, start_new_session=True)
    yield os.read(master, 1000)