GLib.DateTime.prototype.add_weeks
function add_weeks(weeks: Number(gint)): GLib.DateTime {
    // Gjs wrapper for g_date_time_add_weeks()
}
  Creates a copy of datetime and adds the specified number of weeks to the copy. Add negative values to subtract weeks.
Since 2.26
- weeks
 the number of weeks
- Returns
 the newly created GLib.DateTime which should be freed with GLib.DateTime.prototype.unref.