I am completely stuck in **Learn TDD With Mocha**, 4/1.

The error I’m getting is `Did you set three const variables and describe the intended behavior of them using assert.equal?`

, but here is my code:

```
const assert = require('assert');
const Calculate = require('../index.js')
describe('Calculate', () => {
describe('.sum',() => {
it('returns the sum of an array of numbers', () => {
const inputArray = [1, 2, 3]
const expectedResult = 6
const result = Calculate.sum(inputArray)
assert.equal(result, expectedResult)
});
});
});
```

I believe it is right, the code seems pretty valid and the test passes, but it is not being accepted. What is wrong with it?