text: const expect = require('expect');
  const {intersection} = require('./_30s.js');
  
  test('intersection is a Function', () => {
    expect(intersection).toBeInstanceOf(Function);
  });
  test('Returns a list of elements that exist in both arrays', () => {
    expect(intersection([1, 2, 3], [4, 3, 2])).toEqual([2, 3]);
  });
  