System.Collections.Generic.KeyNotFoundException: 'The given key 'Rsqrt' was not present in the dictionary.'

   public override void Train(List<(NDArray,NDArray,  int)>  examples)
        {

            var boards = examples.Select(x => x.Item1).ToArray();
            NDArray input_boards = np.concatenate(boards).reshape((-1,7,7));
        
            NDArray target_pis = np.concatenate(examples.Select(x => x.Item2).ToArray()).reshape((-1,196));
            NDArray target_vs = np.array(examples.Select(x =>(float) x.Item3).ToArray());
            log.Info("Training Net");
            nnet.model.fit( x: input_boards,
                            y: target_pis,
                            batch_size:64
                            );
        }