code: def run(self) -> tuple[list[Node], list[system_message]]:
      target_id = "index-%s" % self.env.new_serialno("index")
      entries = [
          ("single", "RFC; RFC %s" % self.target, target_id, "", None)
      ]
  
      index = addnodes.index(entries=entries)
      target = nodes.target("", "", ids=[target_id])
      self.inliner.document.note_explicit_target(target)
  
      try:
          refuri = self.build_uri()
          reference = nodes.reference(
              "", "", internal=False, refuri=refuri, classes=["rfc"]
          )
          if self.has_explicit_title:
              reference += nodes.strong(self.title, self.title)
          else:
              title = "RFC " + self.title
              reference += nodes.strong(title, title)
      except ValueError:
          msg = self.inliner.reporter.error(
              __("invalid RFC number %s") % self.target,
              line=self.lineno,
          )
          prb = self.inliner.problematic(
              self.rawtext, self.rawtext, msg
          )
          return [prb], [msg]
  
      return [index, target, reference], []
  
imports: from __future__ import annotations
  import re
  from typing import TYPE_CHECKING, Any
  import docutils.parsers.rst.directives
  import docutils.parsers.rst.roles
  import docutils.parsers.rst.states
  from docutils import nodes, utils
  from sphinx import addnodes
  from sphinx.locale import _, __
  from sphinx.util import ws_re
  from sphinx.util.docutils import ReferenceRole, SphinxRole
label_desc: Use image node_id 1 for calling the RFC obj's underlying member method code with example usage: obj.run() and returns: list,  list, list,  list