new_contents: #!/usr/bin/python
  
  import gv
  
  g = gv.digraph("G")
  n = gv.node(g,"hello")
  m = gv.node(g,"world")
  e = gv.edge(n,m)
  gv.layout(g, "dot")
  gv.render(g, "png", "gv_test.png")
  gv.rm(g)
  
subject: add a demo of building a custom python wrapper using libgvc