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-turtle is a module which enables drawings to be made within a DOME script using turtle graphics and the Wren programming language. It consists of two classes: Pen and Turtle, the former representing the latter's pen.
It is the twenty-fifth 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 need to copy the source code (in the talk page) to a text file called turtle.wren and place this in the same directory as the importing script so DOME can find it.
Wren-turtle depends on the graphics and math modules which are part of the DOME framework. As such it can only be used in a DOME script.