Mixtral to NeMo conversion script.
Could you provide the convert NeMo to huggingface script?  @cdj0311 will try to have the NeMo to HF by next week jenkins jenkins jenkins jenkins jenkins jenkins jenkins jenkins Hi @ericharper. I browsed CodeQL suggestions in this pull request. This is a good example when **Flake8** is better than CodeQL: CodeQL fails to detect undefined variables (a simple issue), see `head_num` [here](https://github.com/NVIDIA/NeMo/blob/6865c39d85c4f3b120a02fe74024ad10d5fab286/scripts/nlp_language_modeling/convert_nemo_mixtral_to_hf.py#L124), while Flake8 catches them. I strongly suggest to start using Flake8 complementary to CodeQL in CI.  Another example are the unused imports `from megatron.core.utils import init_method_normal, scaled_init_method_normal` [here](https://github.com/NVIDIA/NeMo/blob/main/nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py#L94). This file is frequently edited btw. Possibly CodeQL misses this due to import guards, but I'm not sure. cc @ericharper 
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