Unit Tests in Serverless / Jest encountered an unexpected token

Hey! Got the error:
notes-app-api@1.1.0 test /home/tuncar/Desktop/AWS/notes-app-api

jest

FAIL tests/billing.test.js
● Test suite failed to run

Jest encountered an unexpected token

This usually means that you are trying to import a file which Jest cannot parse, e.g. it's not plain JavaScript.

By default, if Jest sees a Babel config, it will use that to transform your files, ignoring "node_modules".

Here's what you can do:
 • To have some of your "node_modules" files transformed, you can specify a custom "transformIgnorePatterns" in your config.
 • If you need a custom transformation specify a "transform" option in your config.
 • If you simply want to mock your non-JS modules (e.g. binary assets) you can stub them out with the "moduleNameMapper" config option.

You'll find more details and examples of these config options in the docs:
https://jestjs.io/docs/en/configuration.html

Details:

/home/tuncar/Desktop/AWS/notes-app-api/tests/billing.test.js:1
({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,global,jest){import { calculateCost } from "../libs/billing-lib";
                                                                                                ^

SyntaxError: Unexpected token {

  at ScriptTransformer._transformAndBuildScript (node_modules/@jest/transform/build/ScriptTransformer.js:537:17)
  at ScriptTransformer.transform (node_modules/@jest/transform/build/ScriptTransformer.js:579:25)

Test Suites: 1 failed, 1 total
Tests: 0 total
Snapshots: 0 total
Time: 3.267s
Ran all test suites.
npm ERR! Test failed. See above for more details.

Help me please