Task
📝 **Task:** Function `add(a, b)` should return the sum but returns `None`. Add `return`.
📋 **Steps:**
- Find the `a + b` line missing `return`
- Add `return` before the expression
💡 **Similar example:**
```python
def multiply(x, y):
return x * y
print(multiply(4, 5)) # 20
```
⚠️ A function without `return` ALWAYS returns `None`.
🎯 **Expected output:** `7`