Set light the same brightness

Hey guys!

I want to set up an automation where when a light will be the same brightness as another light.
The reason I want this is that I want 1 light to be brighter, so the plants get more light, but when I press a button it will go back to the same brightness as the other lights.

Currently I got this:

          - service: light.turn_on
              brightness: >
                {{ state_attr('sensor.383a0430ce8afb13927a624532308c27_brightness','brightness')|int }}
              entity_id: light.kantoor_plafond_001

But this doesn’t do anything. Is it because the deviceID for the other light isn’t right?

It’ll be the attribute of the light entity, not a sensor entity.