Importing a class(sample.ts) in code.ts throws error

Recently started to learn Figma Plugin where I could not figure not how to import a sample.ts file in code.ts

example: I had created a file called sample.ts which contains a function

export function testing() { return 'ABC'; }

Adding the following code in code.ts

import { testing } from './sample' console.log(testing())

I see following error in the console
Syntax error on line 80: Unexpected token import { testing } from './sample';

You need to compile the code to a single file instead of keeping them as separate modules.

@Gleb Thank for the response.