Template in blueprint

I have an automation for forwarding graph equalizer band data to light brightness.
Esphome music analyser (work in progress)

I would like to have a blueprint for configuring these automations.
This is the automation:

- id: '1640344277791'
  alias: Disco band 3
  description: ''
  trigger:
  - platform: state
    entity_id: sensor.band_3
  condition: []
  action:
  - service: light.turn_on
    target:
      entity_id: light.band3
    data:
      transition: 0
      color_name: pink
    data_template:
      brightness_pct: '{{ states(''sensor.band_3'') }}
        '
  mode: restart

I have created the following blueprint:

blueprint:
  name: Disco Band automation
  description: Turn a light on based on the musicanalyser sensor
  domain: automation
  input:
    band_sensor:
      name: Band sensor
      description: This is the band sensor of the musicanalyser
      selector:
        target:
          entity:
            domain: sensor
    target_light_group:
      name: Light group
      description: This is the light group to change
      selector:
        target:
          entity:
            domain: light

trigger:
  platform: state
  entity_id: !input band_sensor

action:
  service: light.turn_on
  target:
    entity_id: !input target_light_group
  data:
    transition: 0
    color_name: red
  data_template:
    brightness_pct: '{{ states(''!input band_sensor'') }}'

But when creating the automation I get the error:

Logger: homeassistant.components.automation
Source: components/automation/__init__.py:638
Integration: Automatisering (documentation, issues)
First occurred: 11:12:04 (145 occurrences)
Last logged: 20:00:58

Blueprint Disco Band automation generated invalid automation with inputs OrderedDict([('band_sensor', OrderedDict([('entity_id', 'sensor.band_1')])), ('target_light_group', OrderedDict([('entity_id', 'light.band1')]))]): not a valid value for dictionary value @ data['action'][0]['target']['entity_id']. Got None
Blueprint Disco Band automation generated invalid automation with inputs OrderedDict([('target_color', 'blue'), ('band_sensor', OrderedDict([('entity_id', 'sensor.band_1')])), ('target_light_group', OrderedDict([('entity_id', 'light.band1')]))]): not a valid value for dictionary value @ data['action'][0]['target']['entity_id']. Got None
Blueprint Disco Band automation generated invalid automation with inputs OrderedDict([('band_sensor', OrderedDict([('entity_id', 'sensor.band_1')])), ('target_light_group', OrderedDict([('entity_id', 'light.band1')])), ('target_color', 'blue')]): not a valid value for dictionary value @ data['action'][0]['target']['entity_id']. Got None
Blueprint Disco Band automation generated invalid automation with inputs OrderedDict([('band_sensor', OrderedDict([('entity_id', 'sensor.band_1')])), ('target_light_group', OrderedDict([('entity_id', 'light.band1')])), ('target_color', 'red')]): not a valid value for dictionary value @ data['action'][0]['target']['entity_id']. Got None
Blueprint Disco Band automation generated invalid automation with inputs OrderedDict([('band_sensor', OrderedDict([('entity_id', 'sensor.band_4')])), ('target_light_group', OrderedDict([('entity_id', 'light.aanrecht_links')]))]): not a valid value for dictionary value @ data['action'][0]['target']['entity_id']. Got None

I have tried to put the entity in a var
I have tried to remove the quotes in the data_template around the entity
Who can push me to the right direction?

Home Assistant 2021.12.4

Hi,
Create a variable
variables:
v_band_sensor: !input band_sansor

Replace {{ states(’’!input band_sensor’’) }} by {{ states(v_band_sensor) }}

For the name of the variable you can choose whatever you want, I am using this convention so that “v_” means “declared in variables:”
Rgds.