def url_add_missing_protocol(url, default="http"):
    """
    Adds a protocal to a URL if one is not present

    :param url: URL that may or may not have a protocol.
    :type url: str
    :param default: The protocal to default to if one is not present.
    :type default: str
    :returns: Adds a protocal of http if no protocal present.
    :rtype: str
    """
    if url[:6] != "https:" and url[:5] != "http:":
        url = "%s://%s" % (default, url)
    return url