Home Assistant sensor for IKEA Tradfri feed update check

test.yaml

sensor:
  - platform: command_line
    name: IKEA Tradfri OTA feed
    command: >-
      python3 -c "import hashlib, json, requests; response = requests.get('http://fw.ota.homesmart.ikea.net/feed/version_info.json'); ret = { 'ETag': response.headers.get('ETag'), 'Date': response.headers.get('Date'), 'Hash': hashlib.sha256(response.content).hexdigest() }; print(json.dumps(ret))"
    value_template: '{{ value_json.Hash }}'
    json_attributes:
      - Date
      - ETag
    scan_interval: 10800