src/transformers/models/marian/convert_marian_to_pytorch.py/check_marian_cfg_assumptions
def check_marian_cfg_assumptions(marian_cfg):
    assumed_settings = {
        "layer-normalization": False,
        "right-left": False,
        "transformer-ffn-depth": 2,
        "transformer-aan-depth": 2,
        "transformer-no-projection": False,
        "transformer-postprocess-emb": "d",
        "transformer-postprocess": "dan",  # Dropout, add, normalize
        "transformer-preprocess": "",
        "type": "transformer",
        "ulr-dim-emb": 0,
        "dec-cell-base-depth": 2,
        "dec-cell-high-depth": 1,
        "transformer-aan-nogate": False,
    }
    for k, v in assumed_settings.items():
        actual = marian_cfg[k]
        if actual != v:
            raise ValueError(f"Unexpected config value for {k} expected {v} got {actual}")