Auto Code Commenter
Just give this repl the filepath to your code and it will leave many totally useful comments!
By default it only works with Python code, but it's easy to add your own comment into comments.json, so it can also work with other languages with a bit of modification.
Right now the Auto Commenter will comment on other comments, import statements, print statements, and variable assignments.
If you want to see the output of this repl without forking it to create your own code file, you can just view the test.py file.