title: Change JSON to String
body: <p>I don't have json package.And I create json object and want print it.Is there any way to do this by js native function?
  Or I should write this function by myself?</p>
  
  <p>P.S. I can't import any additional files.And I use Js in program not in browser. JSON is not defined.</p>
  
  <p>Thanks! </p>