I'm trying to add a child node using node-html-parser from this answer

my html file looks like this:

...

 <tbody>
    <tr></tr>
   ...
 </tbody>
    

and node.js app:

const parse = require('node-html-parser').parse;

...

  const doc = parse(fs.readFileSync('./myfile.html','utf8'));
  doc.querySelector("tbody").appendChild("<tr></tr>");

but it's giving an error:

Cannot create property 'parentNode' on string '<tr></tr>'