TF_Tensor** value,
                                                     TF_Status* status);

// Fills in `values` with the TF_Tensor values of the attribute `attr_name` of
// `oper`. `values` must point to an array of TF_Tensor* of length at least
// `max_values` (ideally set to TF_AttrMetadata.list_size from
// TF_OperationGetAttrMetadata(oper, attr_name)).
//

    auto device_value = absl::make_unique<DataType>();
    *device_value = values[device_index];
    std::unique_ptr<TF_Tensor, decltype(&TF_DeleteTensor)> tensor(
        TF_NewTensor(
            datatype_enum, /*dims=*/nullptr, /*num_dims=*/0,
            device_value.release(), sizeof(DataType),
            [](void* data, size_t, void* arg) {
              delete reinterpret_cast<DataType*>(data);
            },

// read current values from streamz counters defined in other modules.
//
// The code under test will have created streamz counters like this:
// auto* streamz = tensorflow::monitoring::Counter<1>::New("name",
// "description", "label");
// and then incremented that counter for various values of label:
// streamz->GetCell("label-value")->IncrementBy(1);
//

  TF_DeleteTensor(t);
  TF_DeleteStatus(status);
  return th;
}

// Return a scalar tensor handle with given values.
template <class T, TF_DataType datatype>
TFE_TensorHandle* TestScalarTensorHandle(TFE_Context* ctx, const T value) {
  T data[] = {value};
  return TestTensorHandleWithDims<T, datatype>(ctx, data, nullptr, 0);
}

// Return a tensor handle containing a 100x100 matrix of floats

TF_CAPI_EXPORT extern uint64_t TF_NowMicros(void);

// Returns the number of seconds since the Unix epoch.
TF_CAPI_EXPORT extern uint64_t TF_NowSeconds(void);

// Populates a TF_ThreadOptions struct with system-default values.
TF_CAPI_EXPORT extern void TF_DefaultThreadOptions(TF_ThreadOptions* options);

// Returns a new thread that is running work_func and is identified
// (for debugging/performance-analysis) by thread_name.
//

                                int num_values) = 0;
  virtual Status SetAttrTypeList(const char* attr_name, const DataType* values,
                                 int num_values) = 0;
  virtual Status SetAttrBoolList(const char* attr_name,
                                 const unsigned char* values,
                                 int num_values) = 0;
  virtual Status SetAttrShapeList(const char* attr_name, const int64_t** dims,

                                                 int num_values);
TF_CAPI_EXPORT extern void TFE_OpSetAttrTypeList(TFE_Op* op,
                                                 const char* attr_name,
                                                 const TF_DataType* values,
                                                 int num_values);
TF_CAPI_EXPORT extern void TFE_OpSetAttrShapeList(

                          int num_values) override;
  Status SetAttrIntList(const char* attr_name, const int64_t* values,
                        int num_values) override;
  Status SetAttrTypeList(const char* attr_name, const DataType* values,
                         int num_values) override;
  Status SetAttrBoolList(const char* attr_name, const unsigned char* values,

                                                 TF_DataType value);
TF_CAPI_EXPORT extern void TF_AttrBuilderSetTypeList(TF_AttrBuilder* builder,
                                                     const char* attr_name,
                                                     const TF_DataType* values,
                                                     int num_values);

// gradient function can accept None values. e.g. FusedBatchNorm outputs 5
// values and hence receives 5 gradient values during backprop. However the
// gradient function uses only the first of those values and ignores the rest.
// The entry, "FusedBatchNorm": [1, 2, 3, 4], indicates that only the gradient
// corresponding to index 0 is used, and the gradient values at indices 1-4 are