I have the book, I have been all over this forum and the documents, I have read the docs, I have googled.
After spending a couple of hours doing that I stumbled over a stackoverflow post that stated that saving a plot is as easy as importing mathplotlib.pyplot and calling mathplotlib.pyplot.savefig(). Please. Add that to the documentation. When a plot or picture is displayed just say that it can be saved using this simple method. Not everyone is on a jupyter notebook. This should also be in the api documents for the various methods (show_results() etc).