如何获取ENVDTE CodeInterface的泛型类型参数？

I'm writing a T4 template in Visual Studio 2010 and am generating code based on existing classes in a project. The code I need to generate depends on the generic type arguments of the interface that the classes implement, but I don't see a way to access that information through the Visual Studio core automation EnvDTE. Here is an example of a class that I need to analyse:I'm writing a T4 template in Visual Studio 2010