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-crypto is a module which implements some of the commoner cryptographic hash algorithms in the Wren programming language. It consists of static methods organized into 8 classes: Bits, Bytes, Md5, Sha256, Sha224, Sha1, Ripemd160 and Hmac. The first two provide utility methods for use by the other six.

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