code: def do_graphviz(self, args, arguments):
          
          filename = arguments['FILENAME']
          if platform.system() == 'Darwin':
              if os.path.isfile(filename):
                  os.system("open -a '\''/Applications/Graphviz.app'\'' " + filename)
docs: ::
          
              Usage:
                     graphviz FILENAME
  
              Export the data in cvs format to a file. Former cvs command
  
              Arguments:
                  FILENAME   The filename