def METHOD_NAME(mcg_obj, workload_bucket, custom_options=None):
    """
    Basic fio configuration for upgrade utilization for NooBaa S3 bucket.
    Args:
        mcg_obj (obj): MCG object, it can be found among fixtures
        workload_bucket (obj): MCG bucket
        custom_options (dict): Dictionary of lists containing tuples with
            additional configuration for fio in format:
            {'section': [('option', 'value'),...],...}
            e.g.
            {'global':[('name','bucketname')],'create':[('time_based','1'),('runtime','48h')]}
            Those values can be added to the config or rewrite already existing
            values
    Returns:
        str: updated fio configuration
    """
    config = configparser.ConfigParser()
    config.read_file(open(constants.FIO_S3))
    config.set("global", "name", workload_bucket[0].name)
    config.set("global", "http_s3_key", mcg_obj.access_key)
    config.set("global", "http_s3_keyid", mcg_obj.access_key_id)
    if mcg_obj.s3_endpoint.startswith("https://"):
        http_host = mcg_obj.s3_endpoint[len("https://") :]
    elif mcg_obj.s3_endpoint.startswith("http://"):
        http_host = mcg_obj.s3_endpoint[len("http://") :]
    else:
        http_host = mcg_obj.s3_endpoint
    config.set("global", "http_host", http_host.rstrip(":443"))
    config.set("global", "http_s3_region", mcg_obj.region)
    config.set("global", "filename", f"/{workload_bucket[0].name}/object")
    config.set("create", "time_based", "1")
    config.set("create", "runtime", "24h")
    # add or overwrite custom values
    if custom_options:
        for section in custom_options:
            if not config.has_section(section):
                config.add_section(section)
            for configuration in custom_options[section]:
                config.set(section, configuration[0], configuration[1])
    return config_to_string(config)