Append nodes after this node.

        If nodes contains ``str``, it will be converted to Text node.

def after(self, *nodes: Union[AbstractNode, str]) -> None:
        """Append nodes after this node.

        If nodes contains ``str``, it will be converted to Text node.
        """
        if self.parentNode:
            node = _to_node_list(nodes)
            _next_node = self.nextSibling
            if _next_node is None:
                self.parentNode.appendChild(node)
            else:
                self.parentNode.insertBefore(node, _next_node)