CheckpointReader::GetVariableToDataTypeMap() const {
  CHECK(var_to_data_type_map_);
  return *var_to_data_type_map_;
}

const string CheckpointReader::DebugString() const {
  if (reader_ != nullptr) return reader_->DebugString();
  return v2_reader_->DebugString();
}

void CheckpointReader::GetTensor(
    const string& name, std::unique_ptr<tensorflow::Tensor>* out_tensor,
    TF_Status* out_status) const {
  Status status;