A Python core developer has requested some changes be made to your pull request before we can consider merging it. If you could please address their requests along with any other requests in other reviews from core developers that would be appreciated.

Once you have made the requested changes, please leave a comment on this pull request containing the phraseI have made the requested changes; please review again. I will then notify any core developers who have left a review that you're ready for them to take another look at this pull request.

This interface is horrible. I see a change was rewuested by@merwok but can't see what it is. So...

I have made the requested changes; please review again.

Thanks for making the requested changes!

@merwok: please review the changes made to this pull request.

I see a change was requested by merwok but can't see what it is. So...

Ah! «requested changes» is a review status (others are «approved» and «commented»)
Comments can be standalone or part of a review; I used the latter mode, made a few comments (some being change suggestions) and published my review with the «changes requested» status. Then I applied some of my suggested changes directly. So you saw «changes requested», some hidden comments («resolved» by the application of the suggestion), and one comment about the wording.

@smontanaro looks good! I tried to do this myself last night, but I was at my kid's soccer practice and discovered that the official iPhone GitHub app does not have all the functionality of the web GUI. 😢

@smontanaro were you responsible for the csv.QUOTE_NULL?

You're an absolute legend!
I am working a project where I need exactly this, thank you so much! :)

Not exactly. Someone else suggested it years ago. I tend to catch most proposed changes to the csv module...