WOW not defined using npm package.

I did this:

npm install wowjs

and required it:

import WOW from 'wowjs

and tried to use it:

let wow = new WOW({
  boxClass: 'wow',
  animateClass: 'animated',
  offset: 0,
  live: true
});

But I got Uncaught ReferenceError: WOW is not defined at console.