Template Light - Support with syntax

I try to create a template light:

light:
  - platform: template
    lights:
      lichterkette_10er:
        friendly_name: "Annas Lichterkette"
        level_template: "{{ states('input_number.spinne_globalbrightness_helper') | int }}"
        value_template: "{{ states('input_number.spinne_globalbrightness_helper') | int > 0 }}"
        effect_list_template: "{{ state_attr('input_select.spinne_effekt', 'options') }}"
        turn_on:
          service: input_number.set_value
          target:
            entity_id: input_number.spinne_globalbrightness_helper
          data:
            value: "{{ 20 | int }}"
        turn_off:
          service: input_number.set_value
          target:
            entity_id: input_number.spinne_globalbrightness_helper
          data:
            value: "{{ 0 | int }}"
        set_level:
          service: input_number.set_value
          target:
            entity_id: input_number.spinne_globalbrightness_helper
          data:
            value: "{{ brightness }}"
        set_effect:
          - service: input_select.select_option
            target:
              entity_id: input_select.spinne_effekt
            data:
              option: "{{ effect }}"

The template in the beginning renders like this in developer tools:

        level_template: "0"
        value_template: "False"
        effect_list_template: "['steady', 'wave', 'cycle', 'pump', 'string', 'dingdong', 'cascade', 'blink']"

When I validate the configuration, I get this error message in developer tools, that I just do not understand

Configuration warnings

Invalid config for 'template' from integration 'light' at configuration.yaml, line 440: some but not all values in the same group of inclusion 'effect' 'lights->lichterkette_10er-><effect>', got None

What is None? Cant it retrieve the list? As far as I understoot, commas are rendered as list here? Or is the problem with the service call?

The entity is not created/present at the moment…

Does anyone have a clue what the error message means/problem is??

Bump🥹. Anyone??

See here: