string compression solutions don't match description

Hello

In the string compression challenge:

- you say `Only compress the string if it saves space.`
- but you have expected outputs like

```python
assert_equal(func('AAABCCDDDDE'), 'A3BC2D4E')
assert_equal(func('BAAACCDDDD'), 'BA3C2D4')
assert_equal(func('AAABAACCDDDD'), 'A3BA2C2D4')
```

The `C2` doesn't save space, right? Shouldn't it be just `CC` ?