mlx safetensors llama Llama-3 instruct finetune chatml DPO RLHF gpt4 synthetic data distillation function calling json mode axolotl merges en dataset:teknium/OpenHermes-2.5 base_model:NousResearch/Hermes-2-Pro-Llama-3-8B base_model:finetune:NousResearch/Hermes-2-Pro-Llama-3-8B region:us