Return Newest Record For an Asset ID

[AKRRMapGuy]

Hello!

I am trying to filter records in a way that shows only the newest record for any given asset ID. For example, Asset 100 has 3 entries in the layer, with dates of 1/1/1999, 2/1/2000 and 1/5/2019 on each record. I want to have an arcade statement return only the record with the newest date IE 1/5/2019. 

I think I am close, but I am getting an error in the Arcade console saying 'GroupBy' is undefined. I can't figure out what the issue is. 

Here's the code I have so far:

var latestByAsset = GroupBy($feature, "AssetID", {
  name: "LatestDate",
  expression: "InspectionDate",
  statistic: "MAX"
});

var newestRecords = [];

// Loop through the grouped results
for (var g in latestByAsset) {
  // Filter the layer to find the record that matches both AssetID and LatestDate
  var matchSet = Filter($feature, "AssetID = @g.AssetID AND DateField = @g.LatestDate");
  var match = First(matchSet);

  // If a match is found, add it to the result
  if (!IsEmpty(match)) {
    Push(newestRecords, match);
  }
}

return newestRecords;

What am I missing?