var rr = Platform.Function.CreateObject("RetrieveRequest");
    Platform.Function.SetObjectProperty(rr, "ObjectType", "DataExtension");


    var sfp = Platform.Function.CreateObject("SimpleFilterPart");
    Platform.Function.SetObjectProperty(sfp, "Property", "DataExtension.CustomerKey");
    Platform.Function.SetObjectProperty(sfp, "SimpleOperator", "equals");
    Platform.Function.AddObjectArrayItem(sfp, "Value", "2512D571-8E5D-43D1-BF65-99666CACB70A");


    Platform.Function.AddObjectArrayItem(rr, "Properties", "Name");
    Platform.Function.AddObjectArrayItem(rr, "Properties", "FieldType");

    Platform.Function.SetObjectProperty(rr, "Filter", sfp);

    var retrieveStatus = [0,0,0];
    var rows = Platform.Function.InvokeRetrieve(rr, retrieveStatus);