def METHOD_NAME(nixtla_results_df, metric=r2_score):
    """Gets the best model based, on lowest error, from a results df
    with a column for each nixtla model.
    """
    best_model, current_accuracy = None, 0
    accuracy_dict = get_model_accuracy_dict(nixtla_results_df, metric)
    for model, accuracy in accuracy_dict.items():
        if accuracy > current_accuracy:
            best_model, current_accuracy = model, accuracy
    return best_model