markdown is not a function

markdown is not a function , though i have installed it using npm install marked In the app.js i have used app.use in which res.local.filterUserHTML is a function, which uses markdown function, But when this is invoked it gives error, stating it doesn't recognize the markdown function.

app.js

const sanitizeHTML = require('sanitize-html')
const markdown = require('marked')

app.use(function(req, res, next) {
  
  res.locals.filterUserHTML = function(content) {
    return sanitizeHTML(markdown(content), {allowedTags: ['bold', 'i'], allowedAttributes: {}})
  }
}

single-post-screen.ejs

...
 <div class="body-content">
    <%- filterUserHTML(post.body) %>
  </div>
...

Output gives an error

TypeError: E:\Web Development\Javascript\Javascript Full Stack from Scratch\ComplexApp\views\single-post-screen.ejs:44
    42| 
    43|   <div class="body-content">
 >> 44|     <%- filterUserHTML(post.body) %>
    45|   </div>
    46| 
    47|   

markdown is not a function
    at Object.res.locals.filterUserHTML (E:\Web Development\Javascript\Javascript Full Stack from Scratch\ComplexApp\app.js:41:25)
    at eval (eval at compile (E:\Web Development\Javascript\Javascript Full Stack from Scratch\ComplexApp\node_modules\ejs\lib\ejs.js:662:12), <anonymous>:47:17)
    at single-post-screen (E:\Web Development\Javascript\Javascript Full Stack from Scratch\ComplexApp\node_modules\ejs\lib\ejs.js:692:17)
    at tryHandleCache (E:\Web Development\Javascript\Javascript Full Stack from Scratch\ComplexApp\node_modules\ejs\lib\ejs.js:272:36)
    at View.exports.renderFile [as engine] (E:\Web Development\Javascript\Javascript Full Stack from Scratch\ComplexApp\node_modules\ejs\lib\ejs.js:489:10)
    at View.render (E:\Web Development\Javascript\Javascript Full Stack from Scratch\ComplexApp\node_modules\express\lib\view.js:135:8)
    at tryRender (E:\Web Development\Javascript\Javascript Full Stack from Scratch\ComplexApp\node_modules\express\lib\application.js:640:10)
    at Function.render (E:\Web Development\Javascript\Javascript Full Stack from Scratch\ComplexApp\node_modules\express\lib\application.js:592:3)
    at ServerResponse.render (E:\Web Development\Javascript\Javascript Full Stack from Scratch\ComplexApp\node_modules\express\lib\response.js:1017:7)
    at exports.viewSingle (E:\Web Development\Javascript\Javascript Full Stack from Scratch\ComplexApp\controllers\postController.js:25:9)

From the docs:

import { marked } from 'marked';
// or const { marked } = require('marked');

const html = marked.parse('# Marked in Node.js\n\nRendered by **marked**.');

So instead of using markdown(), try using markdown.parse().