Fenton/Lee 2 "not yet implemented" comment

Hi :) I saw this in the code:

```
elif self._filter_class == "Fenton/Lee 2": # not yet implemented
```

The comment says "not yet implemented", but in the lines following below the comment, there's code that makes it look like it's implemented.

Is the implementation incorrect or incomplete? Or is the implementation actually complete, making the comment obsolete?