Not a big deal but shouldn't be there after `sum`: <img width="594" alt="image" src="https://user-images.githubusercontent.com/5451366/204344078-c863da87-5532-498f-8cde-7f64e84eef4e.png"> (code taken from [here](https://devblogs.microsoft.com/dotnet/announcing-fsharp-7/#making-working-with-srtps-easier)).
