code: def find_replace(self, node):
          
          newnode = None
          if isinstance(node, nodes.Sequential):
              newnode = self.auto_toc_tree(node)
          elif isinstance(node, nodes.literal_block):
              newnode = self.auto_code_block(node)
          elif isinstance(node, nodes.literal):
              newnode = self.auto_inline_code(node)
          return newnode
docs: Try to find replace node for current node.
  
          Parameters
          ----------
          node : docutil node
              Node to find replacement for.
  
          Returns
          -------
          nodes : node or list of node
              The replacement nodes of current node.
              Returns None if no replacement can be found.