new_contents: #!/usr/bin/env python
  
  import sys
  import mapnik
  
  def render(input_file, output_file, width=800, height=800, bbox=None):
      m = mapnik.Map(width, height)
      mapnik.load_map(m, input_file, False)
      if bbox is not None:
          m.zoom_to_box(bbox)
      else:
          m.zoom_all()
      mapnik.render_to_file(m, output_file)
  
  if len(sys.argv) == 2:
      render(sys.argv[1], "output.png")
  elif len(sys.argv) == 3:
      render(sys.argv[1], sys.argv[2])
  elif len(sys.argv) == 5:
      render(sys.argv[1], sys.argv[2], int(sys.argv[3]), int(sys.argv[4]))
  else:
      print "usage: %s style_file [output_file] [width height]" % sys.argv[0]
      sys.exit(1)
  
subject: Add simple render script.