How to import this in Angular5?

[MichaelLawrenceDee]

By using npm install, I obtained a ts file and a js file.
I tried using the following code in my ts file
import { calculateSize } from 'calculate-size';
but there is no exported module of such. How do I use this exactly? Size does not work either.

[misha130]

import calculateSize from 'calculate-size'
and then just use calculateSize('text', {});