Proper content of localized_content.json

[Vinyasha]

Hello, Charles!

Would you please help me a bit on how to create a proper localized_content.json?
I didn't find anything in the documentation about it.
Currently, I have the following file structure

{
  "handofftest": {
    "articles": [
      {
        "bump_ok": true,
        "comments": "MK",
        "deferred_id": null,
        "en_images": false,
        "hc": "testhc",
        "id": 1111111111111111,
        "locale": "de-de",
        "title": Test Article Title",
        "writer": ""
      },
      1111111111111111
    ]
  }
}

And I've got the following error:

Traceback (most recent call last):
  File "zlo.py", line 81, in <module>
    args.func(args)             # call the default function
  File "zlo.py", line 47, in publish
    ho.register_new_localized_content(deliverable)
  File "C:\Users\m_kopylova\Documents\zlo-master\modules\handoff.py", line 286, in register_new_localized_content
    print(localized_content[article['locale']]['articles'])
KeyError: 'de-de'

I understand that the issue is in JSON content but have no clue how to form it correctly.
Thank you in advance