code: def call_command(self, cmd, *argv):
          
          parser = self.get_parser()
          args = [cmd] + list(argv)
          namespace = parser.parse_args(args)
          self.run_command(namespace)
docs: Runs a command.
  
          :param cmd: command to run (key at the registry)
          :param argv: arguments that would be passed to the command