code: def graph_from_dot_file(path):
      
      
      fd = file(path, 'rb')
      data = fd.read()
      fd.close()
      
      return graph_from_dot_data(data)
docs: Load graph as defined by a DOT file.
      
      The file is assumed to be in DOT format. It will
      be loaded, parsed and a Dot class will be returned, 
      representing the graph.