Now that we have a function to print the grades, let’s create another function to compute the sum of all of the test grades.

This will be super-helpful when we need to compute the average score.

I know what you’re thinking, “let’s just use the built-in `sum`

function!” The built-in function would work beautifully, but it would be too easy.

Computing the sum manually involves computing a rolling sum. As you loop through the list, add the current grade to a variable that keeps track of the total, let’s call that variable `total`

.

### Instructions

**1.**

On line 3, define a function, `grades_sum`

, that does the following:

- Takes in a list of scores,
`scores`

- Computes the sum of the scores
- Returns the computed sum.

Call the newly created `grades_sum`

function with the list of `grades`

and `print`

the result.