def convert_bytes(tot_bytes):
    """Convert bytes to human-readable GB, MB, KB.

    Parameters
    ----------
    tot_bytes : int
        Total number of bytes.

    Returns
    -------
    [GB, MB, KB, rem] : list
        Bytes divided into Giga, Mega, Kilo bytes.
    """
    GB, rem = divmod(tot_bytes, 1024 * 1024 * 1024)
    MB, rem = divmod(rem, 1024 * 1024)
    KB, rem = divmod(rem, 1024)

    return [GB, MB, KB, rem]