mlx safetensors gemma alignment-handbook trl dpo generated_from_trainer text-generation conversational dataset:argilla/dpo-mix-7k base_model:HuggingFaceH4/zephyr-7b-gemma-sft-v0.1 base_model:finetune:HuggingFaceH4/zephyr-7b-gemma-sft-v0.1 license:other model-index region:us