How to mock Request global.Header before executing test cases in jestjs?

Question

So Im unit testing some functions which contains Headers and I've managed to mock the global.Headers by running following code before executing the test.

beforeAll(() => {
  const append = jest.fn();
  // set test `Headers`
  global.Headers = () => ({
    append: append,
  });
});

I'm however trying to mock this within the setup.js, so I don't require to fire make similar beforeAll(()=>{} code for all my test files. I'm not to where I need to point the mock properly, below is what've done.

setup.js

jest.mock(global.Headers, () => {
  global.Headers = () => ({
    append: jest.fn(),
  });
});

---

Update (Found the solution)

Simply do the following in setup.js will work

global.Headers = () => ({
  append: jest.fn(),
});