title: Create JSON Object with Velocity Template Language
body: <p>I am working with the  Apache Velocity Template Language (VTL) in AWS AppSync.
  In my request template I query an undefined amount of items with different elements.
  What I want to do in the response template is to transform the result into a JSON Object which I need later on for my BatchDeleteItem operation.
  This is how I solved it currently:</p>
  
  <pre><code>#set($deleteObject='{"Id" : { "S": "nodelete" },"Sk" : { "S": "nodelete" }}')
  #set($replaceDeleteObject ="")
  #set($separator="")
  
  #foreach( $item in $ctx.result.items )
    #set($replaceDeleteObject = $replaceDeleteObject + $separator + '{"Id" : { "S": "' + $item.Id + '" },"Sk" : { "S": "' + $item.Sk + '" }}')
    #set($separator = ",")
    #set($deleteObject = $replaceDeleteObject)
  #end
  
  $util.qr($ctx.stash.put("deleteObject", $deleteObject))
  </code></pre>
  
  <p>Later on I can access my deleteObject and it works properly. </p>
  
  <p><strong>My question however is</strong>, if it is possible to directly create some kind of JSON Object in vtl in which I can append my values instead of creating this string in the form of a JSON Object?</p>