def _parse_nodes(
        self,
        nodes: Sequence[BaseNode],
        show_progress: bool = False,
        **kwargs: Any,
    ) -> List[BaseNode]:
        """
        Parse document into nodes.

        Args:
            nodes (Sequence[BaseNode]): nodes to parse

        """
        all_nodes: List[BaseNode] = []
        documents_with_progress = get_tqdm_iterable(
            nodes, show_progress, "Parsing documents into nodes"
        )

        for document in documents_with_progress:
            ext = document.metadata.get("extension", "None")
            if ext in FILE_NODE_PARSERS:
                parser = FILE_NODE_PARSERS[ext](
                    include_metadata=self.include_metadata,
                    include_prev_next_rel=self.include_prev_next_rel,
                    callback_manager=self.callback_manager,
                )

                nodes = parser.get_nodes_from_documents([document], show_progress)
                all_nodes.extend(nodes)
            else:
                # What to do when file type isn't supported yet?
                all_nodes.extend(
                    # build node from document
                    build_nodes_from_splits(
                        [document.get_content(metadata_mode=MetadataMode.NONE)],
                        document,
                        id_func=self.id_func,
                    )
                )

        return all_nodes

        Parse document into nodes.

        Args:
            nodes (Sequence[BaseNode]): nodes to parse

        
llama-index-core/llama_index/core/node_parser/file/simple_file.py