# `013` sum of digits

## 📝 Instructions:

1. Complete the `digits_sum()` function. Given a three-digit number, `digits_sum()` finds the sum of its digits.

## 📎 Example input:

```py
digits_sum(123)
```

## 📎 Example output:

```py
6
```

## 💡 Hints:

+ If you don't know how to start solving this assignment, please review the theory for this lesson: https://snakify.org/lessons/integer_float_numbers/

+ You may also try step-by-step theory chunks: https://snakify.org/lessons/integer_float_numbers/steps/1/
