TypeError when trying to create a dashboard using the Custom Strategy full example

As the title indicates I am getting a type error when trying to use the Full Example provided in the developers documentation.

https://developers.home-assistant.io/docs/frontend/custom-ui/custom-strategy/#full-example

The dashboard generates and there is a view for each area but instead of showing each entity i get the following error message in each view:
image

This is my first time working with custom strategies so I may have messed something up. I do not believe that is the case though because I was able to get the mushroom strategy working. I have not made any changes to the example file linked above. I just copied the code into a file in home assistant using Studio Code Server, registered the resource, and created a test dashboard using the specified dashboard configuration.

Any help would be appreciated.

Thanks!

Home Assistant version information:

  • Core: 2024.3.0
  • Supervisor: 2024.02.1
  • Operating System: 12.0
  • Frontend: 20240306.0

This TypeError was resolved with the assistance of karwosts on the Home Assistant discord server.

Karwosts found that there was an error in the code on the developer’s website. They submitted a pull request that can be found here. The documentation has been updated and the code is functioning as expected.