Is it possible to embed an asyncio tcp server as management?

[Zhaoxun]

I want to embed a management tcp service alone with the standard FastAPI service, on a different port and serves localhost only. Let us call it management.py, which will be imported by main.py. Here is a little modification of theTCP echo server using streams
management.py

import asyncio

async def tcp_service(reader, writer):
    data = await reader.read(100)
    message = data.decode()
    addr = writer.get_extra_info('peername')

    print(f"Received {message!r} from {addr!r}")

    print(f"Send: {message!r}")
    writer.write(data)
    await writer.drain()

    print("Close the connection")
    writer.close()
    await writer.wait_closed()

async def tcp_server():
    server = await asyncio.start_server(tcp_service, '127.0.0.1', 9000)
    
    async with server:
        server.serve_forever()  

asyncio.create_task( tcp_server() ) #asyncio.run( tcp_server() )

I tried to run the uvicorn on a different tcp port:
uvicorn main:app --host '0.0.0.0' --port 8000

It loads as if no error. But ss -tlnp shows me that uvicorn only works on 0.0.0.0:8000 without 127.0.0.1:9000
Why is that?