How to use the wikiextractor.extract function in wikiextractor

def extract(output_txt_filepath, spacy_nlp, input_xml_filepath):
    """Extract content of wikipedia XML file.

    Extract content of json.text as given by wikiextractor and tokenize
    content with spacy. Output one-sentence-per-line, lowercase, tokenized
    text.
    """
    logger.info('Extracting content of wikipedia file {}'.format(input_xml_filepath))
    output_filepath = futils.get_output_filepath(input_xml_filepath,
                                                 output_txt_filepath)
    with open(output_filepath, 'w', encoding='utf-8') as output_stream:
        logger.info('Writing output to file {}'.format(output_filepath))
        for json_object in wikiextractor.extract(input_xml_filepath):
            doc = spacy_nlp(json_object['text'])
            for sent in doc.sents:
                output_sent = ' '.join([token.text.lower() for token in sent])
                print(output_sent.strip(), file=output_stream)
                logger.debug('Printed to {}'.format(output_filepath))