Add a "mutex" automation helper

Feature Requests
11

Nope. You just need to learn how. See:

alias: lock1
sequence:
  - wait_template: "{{ is_state('input_text.lock1_owner', '') }}"
    continue_on_timeout: true
    alias: Wait for lock to be available
  - service: input_text.set_value
    data:
      value: "{{ owner }}"
    target:
      entity_id: input_text.lock1_owner
    alias: Set lock owner
mode: queued
fields:
  owner:
    selector:
      text: null
    name: owner
    description: Name of the owner
    required: true