src/transformers/trainer_utils.py/default_hp_space_sigopt
def default_hp_space_sigopt(trial):
    return [
        {"bounds": {"min": 1e-6, "max": 1e-4}, "name": "learning_rate", "type": "double", "transformamtion": "log"},
        {"bounds": {"min": 1, "max": 6}, "name": "num_train_epochs", "type": "int"},
        {"bounds": {"min": 1, "max": 40}, "name": "seed", "type": "int"},
        {
            "categorical_values": ["4", "8", "16", "32", "64"],
            "name": "per_device_train_batch_size",
            "type": "categorical",
        },
    ]