docs: def setup(self):
          """Setup."""
  
          extensions = []
          extension_configs = {}
          for item in self.config['markdown_extensions']:
              if isinstance(item, str):
                  extensions.append(item)
              else:
                  k, v = list(item.items())[0]
                  extensions.append(k)
                  if v is not None:
                      extension_configs[k] = v
          self.markdown = markdown.Markdown(extensions=extensions, extension_configs=extension_configs)