Philips hue, change scene if light is on at sunset

Configuration
1

Hello good folks…

It’s late (at least in Sweden), and I just can’t figure it out…
I got this group of hue lights, group.hue_lights, and I would like to change the scene for any lights that are currently on at sunset?

trigger:
  platform: state
  entity_id: sun.sun
  from: 'above_horizon'
  to: 'below_horizon'
condition: 
  condition: state
  entity_id: group.hue_lights
  state: 'on'
action:
  service: light.hue_activate_scene
  data_template:
    group_name: "<NEED TO GET LIGHT HERE>"
    scene_name: "Sunset"
2

The group_name is used for the room defined in Hue not in HA. Little late response,but I’m a newbie.