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This content is licensed to you under the Creative Commons Attribution (CC BY) license.

An explanation of the license is available here: https://creativecommons.org/licenses/by/4.0/
The full text of the license is available here: https://creativecommons.org/licenses/by/4.0/legalcode

Basically, you can do whatever you want with these, as long as you credit Aaron Teplitsky as the original creator. For full details check out the above links, or the included README file.