Possible to remove the 'internal set' of model properties?

[itb2k13]

I'm building a small home-brew project making use of your great library to interact with Tmdb. Firstly - thanks v much, it works great!

I wish to extend the models slightly to add/set some properties but with the 'internal' modifier I'm not able to. Just wondered if its absolutely necessary to have them like this or you could make them open and extendable models? Would make things a bit easier.