code: def user_role(name, rawtext, text, lineno, inliner, options=None, content=None):
      
      options = options or {}
      content = content or []
      has_explicit_title, title, target = split_explicit_title(text)
  
      target = utils.unescape(target).strip()
      title = utils.unescape(title).strip()
      config = inliner.document.settings.env.app.config
      if config.issues_user_uri:
          ref = config.issues_user_uri.format(user=target)
      else:
          ref = "https://github.com/{0}".format(target)
      if has_explicit_title:
          text = title
      else:
          text = "@{0}".format(target)
  
      link = nodes.reference(text=text, refuri=ref, **options)
      return [link], []
docs: Sphinx role for linking to a user profile. Defaults to linking to
      Github profiles, but the profile URIS can be configured via the
      ``issues_user_uri`` config value.
  
      Examples: ::
  
          :user:`sloria`
  
      Anchor text also works: ::
  
          :user:`Steven Loria <sloria>`