Light dimming with jinja template in scripts.yaml

Configuration
1

Hi!

I’m trying to write a script for slow dimming a light from 50 to 200 brightness.
In a simple way it’s just a set of blocks in scripts.yaml like this:

'1589654337355':
  alias: VR1.LD2 Smooth Maximum
  sequence: 
  - data:
      brightness: 50
    entity_id: light.3431760284f3ebf92381
    service: light.turn_on
  - delay:
      milliseconds: 500
  - data:
      brightness: 51
    entity_id: light.3431760284f3ebf92381
    service: light.turn_on
  - delay:
      milliseconds: 500
...
  - data:
      brightness: 200
    entity_id: light.3431760284f3ebf92381
    service: light.turn_on

But this needs too much text for this simple task. So I’ve decided to optimize it with templating:

'1589654337355':
  alias: VR1.LD2 Smooth Maximum
  sequence: {% for br in range(50,200,1) -%}{% raw %}
  - data:
      brightness: {% endraw %}{{br}}{% raw %}
    entity_id: light.3431760284f3ebf92381
    service: light.turn_on
  - delay:
      milliseconds: 500
{% endraw %}{%- endfor %}

This works as expected in template editor, but pasting this to scripts.yaml causes error

Error loading /config/configuration.yaml: while scanning for the next token found character '%' that cannot start any token in "/config/scripts.yaml", line 3, column 14

Next I’ve tried to make quotes around template items:

'1589654337355':
  alias: VR1.LD2 Smooth Maximum
  sequence: "{% for br in range(50,200,1) -%}{% raw %}"
  - data:
      brightness: "{% endraw %}{{br}}{% raw %}"
    entity_id: light.3431760284f3ebf92381
    service: light.turn_on
  - delay:
      milliseconds: 500
"{% endraw %}{%- endfor %}"

But this causes error:

Error loading /config/configuration.yaml: while parsing a block mapping in "/config/scripts.yaml", line 2, column 3 expected <block end>, but found '-' in "/config/scripts.yaml", line 4, column 3

Will be very pleased if you can recommend me correct format for template in scripts.yaml or give a sample code for similar task

Thank you!