a python script to archive file hashes

When I teach, I often show diagrams, and I tell the students to email me if they want to see what code I used to create those diagrams. If they do it on the day of class, I'll remember which graph they mean. But if they email weeks later, saying something like "the graph with red contours" then I won't remember. So I wrote a utility that makes sha1 hash codes for the source files, so that I can put the first few characters of the code on the graph. That way, they just have to jot down a few characters in their notes, and if they tell me those characters, I can know what file to send them. This utility copies the file (so I don't have to worry about revising it later) and stores the filenames, dates, and comments, in a csv file. In the video I walk through the process. The file is at github.com/dan...