code: function extend(object, properties) {
    object = object || { };
    const anotherObject = properties || { };
  
    for (const key in anotherObject) {
      const val = anotherObject[key];
  
      if (val || (val === '')) {
        object[key] = val;
      }
    }
    return object;
  }
docs: utility method for extending an object definition