The worst is when someone puts **kwargs at the base of a class hierarchy, not only necessitating its use in subclasses (if you want to be strict about types) bu

The worst is when someone puts **kwargs at the base of a class hierarchy, not only necessitating its use in subclasses (if you want to be strict about types) but also swallowing errors for no good reason. Fortunately I think this style is fading out as type hints become more popular.