code: def complete_help_subcommand(self, text: str, line: str, begidx: int, endidx: int) -> List[str]:
          
  
          # Get all tokens through the one being completed
          tokens, _ = self.tokens_for_completion(line, begidx, endidx)
  
          if not tokens:
              return []
  
          # Must have at least 3 args for 'help command sub-command'
          if len(tokens) < 3:
              return []
  
          # Find where the command is by skipping past any flags
          cmd_index = 1
          for cur_token in tokens[cmd_index:]:
              if not cur_token.startswith('-'):
                  break
              cmd_index += 1
  
          if cmd_index >= len(tokens):
              return []
  
          command = tokens[cmd_index]
          matches = []
  
          # Check if this is a command with an argparse function
          func = self.cmd_func(command)
          if func and hasattr(func, 'argparser'):
              completer = AutoCompleter(getattr(func, 'argparser'), self)
              matches = completer.complete_command_help(tokens[cmd_index:], text, line, begidx, endidx)
  
          return matches
docs: Completes the subcommand argument of help