code: def commandline (self, argv):
          
          self.invoke_with_usage (argv[1:],
                                  tool=self,
                                  argv0=self.cli_name)
docs: Run as if invoked from the command line. 'argv' is a Unix-style list of
          arguments, where the zeroth item is the program name (which is ignored
          here). Usage help is printed if deemed appropriate (e.g., no arguments
          are given). This function always terminates with an exception, with
          the exception being a SystemExit(0) in case of success.
  
          Note that we don't actually use `argv[0]` to set `argv0` because it
          will generally be the full path to the script name, which is
          unattractive.