docs: public SDVariable constant(String name, @NonNull INDArray constant){
          Preconditions.checkState(!variables.containsKey(name), "Variable with name \"%s\" already exists", name);
          if (name == null || name.length() < 1)
              name = getNewVarName();
          SDVariable v = new SDVariable(name, VariableType.CONSTANT, this, constant.shape(), constant.dataType(), null);
          variables.put(name, Variable.builder().name(name).variable(v).build());
          constantArrays.put(name, new DeviceLocalNDArray(constant));
          return v;
      }