code: def tilelayer_preview(tilelayer):
      
      output = '<img src="{src}" alt="{alt}" title="{title}" />'
      url = tilelayer.url_template.format(s="a", z=9, x=265, y=181)
      output = output.format(src=url, alt=tilelayer.name, title=tilelayer.name)
      return output
docs: Return an <img> tag with a tile of the tilelayer.