code: function stamp(obj) {
      if (!obj.__fe_id) {
          lastId += 1;
          obj.__fe_id = lastId; // eslint-disable-line camelcase
      }
  
      return obj.__fe_id;
  }
docs: Assign a unique id to an object
  @param {object} obj - Object that will be assigned id.
  @returns {number} Stamped id
  @memberof tui.util