def create_mac_string(num, splitter=':'):
    """Return the mac address interpretation of num,
    in the form eg '00:11:22:33:AA:BB'.

    :param num: a 48-bit integer (eg from uuid.getnode)
    :param spliiter: a string to join the hex pairs with
    """

    mac = hex(num)[2:]

    # trim trailing L for long consts
    if mac[-1] == 'L':
        mac = mac[:-1]

    pad = max(12 - len(mac), 0)
    mac = '0' * pad + mac
    mac = splitter.join([mac[x:x + 2] for x in range(0, 12, 2)])
    mac = mac.upper()

    return mac