title: What is the purpose of the HTML attribute data-sheets-userformat?
body: <p>I am writing a script to migrate a WordPress site to a custom CMS. Within some of the post content there is some HTML that I don't understand.</p>
  
  <p>What is the purpose of the data-sheets-userformat attribute?
  <code>data-sheets-userformat='[null,null,14781,[null,2,"@",1], ...</code></p>