Trying to write a template that returns all skipped updates

Configuration
1

I want a list with the entity_ids of all entities that skipped an update. I tried a lot that looks similar to

{{
  states.update 
  | selectattr('attributes.in_progress', 'eq', false) 
  | rejectattr('state', 'eq', 'unavailable') 
  | rejectattr('skipped_version', 'eq', 'null') 
  | sort(attribute='entity_id', reverse=false) 
  | map(attribute='entity_id') 
  | list 
}}

but I can’t get it to work. It is as if that attribute skipped_version doesn’t exist at all.

This works:

type: custom:auto-entities
filter:
  include:
    - domain: update
      name: Esph*
      attributes:
        in_progress: false
      options:
        type: tile
        state_content:
          - installed_version
          - skipped_version
  exclude:
    - attributes:
        skipped_version: null
    - state: unavailable
show_empty: true
card:
  type: vertical-stack
  title: ''
card_param: cards
sort:
  method: entity_id
  reverse: false
  count: 500
layout_options:
  grid_columns: 4
  grid_rows: 1

but I need it as a template not a card.

2 
| rejectattr('attributes.skipped_version', 'eq', none)
3

YES!!
Thank you!!