mlx safetensors mistral Mistral instruct finetune chatml DPO RLHF gpt4 synthetic data distillation function calling json mode en dataset:teknium/OpenHermes-2.5 base_model:mistralai/Mistral-7B-v0.1 base_model:finetune:mistralai/Mistral-7B-v0.1 license:apache-2.0 region:us