code: @Override
      public void createMessages(VarTensor[] inMsgs, VarTensor[] outMsgs) {
          Identity<MVecArray<VarTensor>> modIn = new Identity<MVecArray<VarTensor>>(new MVecArray<VarTensor>(inMsgs));
          MutableModule<MVecArray<VarTensor>> modOut = getCreateMessagesModule(modIn, null);
          modOut.setOutput(new MVecArray<VarTensor>(outMsgs));
          modOut.forward();
      }
docs: TODO: This could be put in an abstract class.