def flatten_results(results: dict, derivation_config: dict) -> dict:
    """Flatten and simplify the results dict into <metric>:<result> format.

    Args:
        results (dict): The benchmark results dict, containing all info duch as
            reduction types too
        derivation_config (dict): The configuration defining how metrics are
            derived from logs

    Returns:
        flat_results (dict): The flattened dict of all results in
            <metric>:<result> format

    """

    flat_results = {}
    for metric, results_dict in results.items():
        key = derivation_config.get(metric, {}).get("reduction_type", "mean")
        flat_results[metric] = results_dict[key]

    return flat_results