Sensor Template Icons

Hello.
I’m trying to figure out how to define which Icon that will be used in a Sensor Template.

This is my sensor template.

{{ iif(is_state(‘binary_sensor.peters_telefon_device_locked’, ‘on’), ‘Locked’, ‘Unlocked’) }}

the sensor is made to change the status of On and Off to Locked and Unlocked.
But I would also like it to change the Icon based on the state.

Thanks for any tips.

Hello Bob,

You should make a template sensor for that entity.
Search this and you will see examples:

site:home-assistant.io change icon template sensor

Thank you.
This is how It ended up working.

- sensor:
    - name: petertelefonlocked
      unique_id: peter_telefon_locked
      state: >
        {% if is_state("binary_sensor.peters_telefon_device_locked", "on") %}
        Locked
        {% else %}
        Unlocked
        {% endif %}
      icon: >
        {% if is_state("binary_sensor.peters_telefon_device_locked", "on") %}
          mdi:lock-outline
        {% else %}
          mdi:lock-open-variant-outline
        {% endif %}