How to use the @ember/test-helpers.setApplication function in @ember/test-helpers

pauseTest,
    resumeTest,
    waitFor,
    waitUntil,
    settled,
    isSettled,
    getSettledState,
    visit,
    currentURL,
    currentRouteName,
    setApplication
} from '@ember/test-helpers';

const MyApp = Application.extend({ modulePrefix: 'my-app' });

setApplication(MyApp.create());

test('DOM interactions', async () => {
    await render(hbs`<div class="message">Hello, world</div>`);

    await click('.message');
    await doubleClick('.message');
    await tap('.message');
    await focus('.message');
    await blur('.message');
    await triggerEvent('.message', 'custom-event');
    await triggerKeyEvent('.message', 'keydown', 'Enter', { ctrlKey: true });
    await fillIn('.message', 'content');

    const messageElement = find('.message')!;
    await click(messageElement);
    await doubleClick(messageElement);

import Application from '../app';
import config from '../config/environment';
import { setApplication } from '@ember/test-helpers';
import { start } from 'ember-qunit';
import loadEmberExam from 'ember-exam/test-support/load';

setApplication(Application.create(config.APP));

start();
loadEmberExam();

import { setApplication } from '@ember/test-helpers';
import { start } from 'ember-qunit';
import Application from '../app';

setApplication(Application.create({ autoboot: false }));
start();

import Application from '../app';
import config from '../config/environment';
import { setApplication } from '@ember/test-helpers';
import { start } from 'ember-qunit';

setApplication(Application.create(config.APP));

start();

import Application from '../app';
import config from '../config/environment';
import { setApplication } from '@ember/test-helpers';
import { start } from 'ember-qunit';

setApplication(Application.create(config.APP));

start();

import Application from '../app';
import config from '../config/environment';
import { setApplication } from '@ember/test-helpers';
import { start } from 'ember-qunit';

setApplication(Application.create(config.APP));

start();

import Application from '../app';
import config from '../config/environment';
import { setApplication } from '@ember/test-helpers';
import { start } from 'ember-qunit';

setApplication(Application.create(config.APP));

start();

import Application from '../app';
import config from '../config/environment';
import { setApplication } from '@ember/test-helpers';
import { start } from 'ember-qunit';

setApplication(Application.create(config.APP));

start();

import Application from '../app';
import config from '../config/environment';
import { setApplication } from '@ember/test-helpers';
import { start } from 'ember-qunit';

setApplication(Application.create(config.APP));

start();

import Application from '../app';
import config from '../config/environment';
import { setApplication } from '@ember/test-helpers';
import { start } from 'ember-qunit';

setApplication(Application.create(config.APP));

start();