def METHOD_NAME(dirname, model_name):
    """
    gets files of the form:
     - modelname + '_xxx.flo'
    """
    flo_filenames = os.listdir(dirname)
    n_list = []
    # get the max N value
    for flo_filename in flo_filenames:
        base, ext = os.path.splitext(flo_filename)
        if ext == '.flo' and '.aux.' not in flo_filename:
            if '_' not in flo_filename:
                print(flo_filename)
                continue
            n = int(base.split('_')[-1])
            n_list.append(n)
    n_list.sort()
    return n_list