def METHOD_NAME(device_name, netmiko_results):
    results_file = "netmiko_performance.csv"
    file_exists = os.path.isfile(results_file)
    with open(results_file, "a") as csv_file:
        field_names = ["date", "netmiko_version", "device_name"] + list(
            netmiko_results.keys()
        )
        t_stamp = generate_csv_timestamp()
        csv_write = csv.DictWriter(csv_file, fieldnames=field_names)
        # Write the header only once
        if not file_exists:
            csv_write.writeheader()
        entry = {
            "date": t_stamp,
            "netmiko_version": __version__,
            "device_name": device_name,
        }
        for func_name, exec_time in netmiko_results.items():
            entry[func_name] = exec_time
        csv_write.writerow(entry)