I challenged Daniel Shiffman and here’s his response

This year I donated $700 to the Processing Foundation to support people who care about the development of the projects. To my surprise, Daniel Shiffman personally contacted me and offered to publish a tutorial on a topic of my choice. I wrote him that it would be great if he would explain the copy function. Here is the result.

Dear Daniel, thank you from the bottom of my heart for your generous support and I hope we will get to know each other someday.