SSJS: Update a Data Extension with a value

<script runat="server">

    Platform.Load("Core", "1");

    var proxy = new Script.Util.WSProxy();

    var updateDEFields = function() {

        var deKey = "ExampleDE";

        var emailValue = "example@example.com";

        var deObject = {

            CustomerKey: deKey,

            Keys: [

                { Name: "EMAIL", Value: emailValue }

            ],

            Properties: [

                { Name: "NumberField", Value: null }, 

                { Name: "AnotherField", Value: "New Value" }, 

                { Name: "YetAnotherField", Value: "Another New Value" } 

            ]

        };

        var updateOptions = {};

        try {

            Write("Attempting to update Data Extension...<br>");

            Write("Data Extension Object: " + Stringify(deObject) + "<br>");

            Write("Update Options: " + Stringify(updateOptions) + "<br>");

            var result = proxy.updateItem("DataExtensionObject", deObject, updateOptions);

            Write("Update call result: " + Stringify(result) + "<br>");

            if (result.Status === "OK") {

                Write("<br>Status: " + result.Results[0].StatusMessage);

                Write("<br>Request ID: " + result.RequestID);

            } else {

                Write("<br>Error Status: " + result.Status);

                Write("<br>Error Status Message: " + result.Results[0].StatusMessage);

                Write("<br>Request ID: " + result.RequestID);

            }

        } catch (e) {

            Write("<br>Error: " + e.message);

            Write("<br>Stack Trace: " + e.stack);

        }

    };

    updateDEFields();

</script>