Code.gs

function sentiment_analysis(content) {
  var URL = "https://us-central1-mw-automl-first-look.cloudfunctions.net/analyze"   
  var options = {
    'method' : 'post',
    'contentType': 'application/json',
    // Convert the JavaScript object to a JSON string.
    'payload' : JSON.stringify({"content": content})
  };
  return UrlFetchApp.fetch(URL, options).getContentText();
}