convert notion page to markdown

import { Client } from '@notionhq/client';

import { NotionToMarkdown } from 'notion-to-md';

export async function main(appToken: string, pageId: string) {

 return new Promise(async (resolve, reject) => {

  let notion = new Client({

    auth: appToken

  });

  const n2m = new NotionToMarkdown({ notionClient: notion });

  const markdown = await n2m.pageToMarkdown(pageId)

  .catch((err) => {

    reject(err);

    return 

  });

  if (!markdown) {

    reject("Failed to convert page to markdown");

    return 

  }

  resolve(n2m.toMarkdownString(markdown))

  return

 })

}