docs: function mapProperties(obj, func) {
      if (_.isArray(obj)) {
          throw new Error(`Input must be an object: ${obj}`);
      }
      else {
          const resultObj = Object.create(Object.prototype);
          for (const key in obj) {
              if (obj.hasOwnProperty(key)) {
                  resultObj[key] = func(obj[key], key);
              }
          }
          return resultObj;
      }
  }