The workaround for me right now is calling Python wrapper function that returns new instance of this class.
IntPtr pyobj = default(IntPtr);
IntPtr u_name = Runtime.PyUnicode_FromString(ModuleName);
IntPtr module = Runtime.PyImport_Import(u_name);
IntPtr pyclass = Runtime.PyObject_GetAttrString(module, ObjectName);
if (Runtime.PyCallable_Check(pyclass) == 1)
{
pyobj = Runtime.PyObject_CallObject(pyclass, pyargtuple);
}
IntPtr inst = Runtime.PyObject_Call(pyobj, IntPtr.Zero);
PyObject result = new PyObject(inst);
return result;