text: def organize_media_by_event(eventmedia_queryset):
      """Organizes event media by event.
  
      Given a queryset of event media, it returns a list of 'objects'
      with the following properties:
  
      * event (event object)
      * date (date object for most recently posted media from event)
      * media_list (a string of the available media types)
      """
  
      media_by_event = {}
      for media in eventmedia_queryset:
          media_by_event.setdefault(media.event.id, []).append(media)
      mbe = [{'event': x[0].event,
              'date': max(y.date_created for y in x),
              'media_list': ', '.join(set(y.get_format_display() for y in x))}
             for x in media_by_event.values()]
      mbe.sort(key=(lambda x: x['date']), reverse=True) # sort by date
      return mbe
  