* must be less than 2,048 characters.
     */
    private String loc;

    /**
     * The date of last modification of the file. This date should be in W3C
     * Datetime format. This format allows you to omit the time portion, if
     * desired, and use YYYY-MM-DD.
     *
     * Note that this tag is separate from the If-Modified-Since (304) header
     * the server can return, and search engines may use the information from