Flipping a switch from remote rPI

Configuration
1

I have 1 rPi running hassio, and I want to have several more running a custom GUI from which I can control my hassio.
So currently I’m trying to control 1 light from remote rPI with the REST API ( https://developers.home-assistant.io/docs/en/external_api_rest.html )
I’m able to get states, but I can’t “flip the switch”

import requests

url = "http://192.168.1.225:8123/api/states/switch.ghlinks"
headers = {
    "Authorization": "Bearer ABCDE",
    "content-type": "application/json",
}
myobj = '{"state": "on"}'

response = requests.post(url, headers=headers, data = myobj)

print(response.text)

the state is changed, but the light doesn’t come on (or off)
How do I do this?

2

API call should be to http://192.168.1.225:8123/api/services/light/turn_on then pass entity as data if this call is to HA endpoint.

EDIT
Or api/services/homeassistant/turn_on since it is switch not light

3

My Garage RPI Player just runs a mqtt pub (a poor single cmd nothing with python import json overkill) to tell his amp to shutoff or power on.
fast simple and bulletproof

4

Thanks for the help, and for future reference: the right code was
http://192.168.1.225:8123/api/services/switch/turn_off

import requests

url = "http://192.168.1.225:8123/api/services/switch/turn_off"
#url = "http://192.168.1.225:8123/api/states"
headers = {
    "Authorization": "Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJpc3MiOiI3YTU1MzRhZWFiMmQ0MjE4YWIyNWMyY2U2MGUxMjQ3MiIsImlhdCI6MTU3OTY5eNDI5NywiZXhwIjoxODk1MDU0Mjk3fQ.uNYhEX9lg24H09UQLJtT7wQfcCwclG7POtrGGbEiqvc",
    "content-type": "application/json",
}
myobj = '{"entity_id": "switch.relais_3"}'

response = requests.post(url, headers=headers, data = myobj)
#response = requests.get(url, headers=headers)
print(response.text)