Re. https://codereview.stackexchange.com/a/261457/25834
It was deleted due to the appearance that it was an alternate solution with no explanation. But I would have accepted the author's
> We are using pd.Grouper which is much faster compared to resample when used with groupby.
as sufficient explanation/insight. So I think that it's unfortunate that it got deleted. is this worth undeleting, or would that be inappropriate?