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As a follow-up to Raymond's suggestion, I am attaching a patch that will add a sidebar to the introduction section of the turtle documentation section. While it is not common to include screenshots in python documentation, I think it is very appropriate for a visual module such as turtle. I considered a "Basic example" subsection similar to that in unittest module documentation, but turtle introduction already has a basic example (forward(15); left(25) embedded in the prose, so I think a sidebar like this is more appropriate. 
Since svn does not include binary files in the patch, I will have to attach the embedded image separately. I will also post a screenshot of the rendered HTML page.