From Rosetta Code
This is an example of a library. You may see a list of other libraries used on Rosetta Code at Category:Solutions by Library.

Wren-llist is a module which adds linked list support to the Wren programming language. It consists of 4 classes: LinkedList, DLinkedList, Node and DNode. The first two of these represent singly-linked and doubly-linked lists respectively. The last two represent their corresponding node types and should not need to be imported directly by the user unless they are used for other purposes.

It is the fourteenth in a series of modules (listed on the language's main page) designed to assist with writing Rosetta Code tasks so the same code does not have to be written or copy/pasted time and time again thereby bloating a task's script code unnecessarily.

To use it you all you need to do is to copy the source code (in the talk page) to a text file called llist.wren and place this in the same directory as the importing script so the command line interpreter can find it.