PythonEngine.Initialize() failed when anonymous type found in referenced assembly. In method GenericUtil.Register(Type t) there is no test for types which t.Namespace is null. When t.Namespace is null attempt to get it from dictionary 'maping' failed with message "Value cannot be null". Anonymous types are declared e.g. in Autofac.dll (wide use IoC container). Simple correction is just check if t.Namespace is null and then don`t process that type.
The patch fixes this bug.