title: Error 401 when connecting to external API Google Apps Script
body: <p>I'am trying to retrieve some data from Klipfolio and put it in a Google Spreadsheet. I'am using Google Apps Script to accomplish this, but I get this error: </p>
  
  <blockquote>
    <p>Errorcode: 401.
    {"meta:{"success":false,"status":401,"error_code":"auth_not_provided","error_desc":"This
    operation requires authentication"}}</p>
  </blockquote>
  
  <p>this is my code:</p>
  
  <pre><code>function output() {
    var url = "https://app.klipfolio.com/api/1.0/klips/db88d343e7eeef916f9541d73f0df58c/schema/";
    var response = UrlFetchApp.fetch(url);
    var json = response.getContentText();
    var data = JSON.parse(json);
    return data;
  }
  </code></pre>
  
  <p>I hope you can help me...</p>