def benchmark(benchmark_name):
    """
    Utility function to be used as input to various SampleAugmenter functions, specifying a single parameter benchmark.

    Parameters
    ----------
    benchmark_name : str
        Name of the benchmark (as in `madminer.core.MadMiner.add_benchmark`)


    Returns
    -------
    output : tuple
        Input to various SampleAugmenter functions

    """
    return 'benchmark', benchmark_name
