无法使用存储属性“description”重写

I have an object class of NotSureItem in which I am adding some attribute of item. In my app I am using Realm for database but when I added the the description attributes in my app its shows me an error of overriding the stored property. And It also giving some error like this 'Getter for 'description' with Objective-C selector 'description' conflicts with getter for 'description' from superclass 'NSObject' with the same Objective-C selector'. Here its my code object class.I have an object class of NotSureItem in which