code: def do_verbose(self, args, arguments):
          
          if args == '':
              self.echo = not self.echo
          else:
              self.echo = arguments['True']
docs: Usage:
              verbose (True | False)
              verbose
  
          If it sets to True, a command will be printed before execution.
          In the interactive mode, you may want to set it to False.
          When you use scripts, we recommend to set it to True.
  
          The default is set to False
  
          If verbose is specified without parameter the flag is
          toggled.