langchain/document_loaders/evernote.py/EverNoteLoader/_parse_note_xml
class EverNoteLoader:    def _parse_note_xml(xml_file: str) -> Iterator[Dict[str, Any]]:
        """Parse Evernote xml."""
        # Without huge_tree set to True, parser may complain about huge text node
        # Try to recover, because there may be "&nbsp;", which will cause
        # "XMLSyntaxError: Entity 'nbsp' not defined"
        try:
            from lxml import etree
        except ImportError as e:
            logging.error(
                "Could not import `lxml`. Although it is not a required package to use "
                "Langchain, using the EverNote loader requires `lxml`. Please install "
                "`lxml` via `pip install lxml` and try again."
            )
            raise e

        context = etree.iterparse(
            xml_file, encoding="utf-8", strip_cdata=False, huge_tree=True, recover=True
        )

        for action, elem in context:
            if elem.tag == "note":
                yield EverNoteLoader._parse_note(elem)