docs: def make_request(url, data, on_complete):
      """
      Make AJAX request to `url` with given POST `data`. Call `on_complete`
      callback when complete.
  
      Args:
          url (str): URL.
          data (dict): Dictionary with POST data.
          on_complete (ref): Reference to function / method which will be called
              when the request is done.
      """
      req = ajax.ajax()
      req.bind('complete', on_complete)
      req.open('POST', url, True)
      req.set_header('content-type', 'application/x-www-form-urlencoded')
      req.send(data)