In [commit 6072ad4](6072ad4), @KajvanRijn kindly changed all "TO DO" to "TODO" in the code blocks. That's useful. In addition, it should be changed (as here) in the instructions. Then there's no doubt or issue for anyone searching all instances.
I added a little code to include a vertical dashed line on the plot representing where total_weights = number of train observations. I also moved n_epochs as an argument to fit_model() so learners can play around with the impact of n_epochs more easily.
