Efficient dialog data format for KTO training

I have dialogs in the shareGPT format (see below) and for each `gpt` turn a label (thumbs up or thumbs down). But for KTO training, I have only seen datasets with the columns `prompt`, `completion` and `label` (see e.g. https://huggingface.co/datasets/trl-lib/kto-mix-14k).

Do I need to unwind my shareGPT dialogs (see below) for KTO training, or is there some more efficient format I can use?

How should the dialog history be encoded in the `prompt` column (see below)?

shareGPT-Format:
```
{"conversations":[
{"from":"system","value":"You are a friendly assistant for ....\n"},
{"from":"human","value":"Hello, I am Sam and ..."},
{"from":"gpt","value":"Welcome Sam, so you ...."},
{"from":"human","value":"Yes, but ...."},
{"from":"gpt","value":"Then ..."}
]}
```

Transformed to KTO, with `prompt` column as close as possible to https://huggingface.co/datasets/trl-lib/kto-mix-14k:
```
prompt, completion, label
[ { "content": "You are a friendly assistant for ....\n", "role": "system" }, { "content": "Hello, I am Sam and ...", "role": "human" }], {"role":"gpt","content":"Welcome Sam, so you ...."}, true
[ { "content": "You are a friendly assistant for ....\n", "role": "system" }, { "content": "Hello, I am Sam and ...", "role": "human" }, {"role":"gpt","content":"Welcome Sam, so you ...."}, {"role":"human","content":"Yes, but ...."}], {"role":"gpt","content":"Then ..."}, false
``