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#
# Licensed under the Apache License, Version 2.0 (the "License");
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# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
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def get_weight_loader(arch: str):
    from verl.models.mcore.loader import load_state_dict_to_megatron_gptmodel

    _MODEL_WEIGHT_MEGATRON_LOADER_REGISTRY = {
        "LlamaForCausalLM": load_state_dict_to_megatron_gptmodel,
        "Qwen2ForCausalLM": load_state_dict_to_megatron_gptmodel,
    }

    if arch in _MODEL_WEIGHT_MEGATRON_LOADER_REGISTRY:
        return _MODEL_WEIGHT_MEGATRON_LOADER_REGISTRY[arch]
    raise ValueError(f"Model architectures {arch} loader are not supported for now. Supported architectures: {_MODEL_WEIGHT_MEGATRON_LOADER_REGISTRY.keys()}")


def get_weight_saver(arch: str):
    from verl.models.mcore.saver import merge_megatron_ckpt_gptmodel, merge_megatron_ckpt_gptmodel_mixtral, merge_megatron_ckpt_gptmodel_qwen_moe

    _MODEL_WEIGHT_MEGATRON_SAVER_REGISTRY = {
        "LlamaForCausalLM": merge_megatron_ckpt_gptmodel,
        "Qwen2ForCausalLM": merge_megatron_ckpt_gptmodel,
        "MixtralForCausalLM": merge_megatron_ckpt_gptmodel_mixtral,
        "Qwen2MoeForCausalLM": merge_megatron_ckpt_gptmodel_qwen_moe,
        "Qwen3ForCausalLM": merge_megatron_ckpt_gptmodel,
        "Qwen3MoeForCausalLM": merge_megatron_ckpt_gptmodel_qwen_moe,
    }
    if arch in _MODEL_WEIGHT_MEGATRON_SAVER_REGISTRY:
        return _MODEL_WEIGHT_MEGATRON_SAVER_REGISTRY[arch]
    raise ValueError(f"Model architectures {arch} saver are not supported for now. Supported architectures: {_MODEL_WEIGHT_MEGATRON_SAVER_REGISTRY.keys()}")