def return_filename_filter_string(settings):
    """Returns a list of dicts with, a key/value for the search string.
    This string is used to filter the log files based on the command line
    parameters.
    """
    searchstrings = []

    rw = settings['rw']
    iodepths = settings['iodepth']
    numjobs = settings['numjobs']
    benchtypes = settings['type']

    for benchtype in benchtypes:
        for iodepth in iodepths:
            for numjob in numjobs:
                searchstring = f"{rw}-iodepth-{iodepth}-numjobs-{numjob}_{benchtype}"
                attributes = {'rw': rw, 'iodepth': iodepth,
                              'numjobs': numjob, 'type': benchtype,
                              'searchstring': searchstring}
                searchstrings.append(attributes)
    return searchstrings