I've realised it won't be that easy to handle `*args`, so yes, the `transform` and `inverse_transform` methods of `SelectorMixin` would need to be overwritten. If you think it's necessary I can add that to the patch.

It's not like it's hard for users to retrieve the mask in any case; an integer index can be retrieved with `obj.transform(np.arange(num_input_features))`.