const string sep =
      name_.empty() || unique_name.empty() ? "" : kScopeSeparator;
  return strings::StrCat(name_, sep, unique_name);
}

string Scope::GetUniqueNameForOp(const string& default_name) const {
  if (impl()->single_use_scope()) {
    if (impl()->op_name_.empty() || *impl()->scope_used_) {
      *impl()->status_ =

  // The following functions are for scope object consumers.

  /// Return a unique name, using default_name if an op name has not been
  /// specified.
  string GetUniqueNameForOp(const string& default_name) const;

  /// Update the status on this scope.
  /// Note: The status object is shared between all children of this scope.

  }

  strings::StrAppend(&body, "  ::tensorflow::Node* ret;\n");
  strings::StrAppend(&body, "  const auto unique_name = ", scope_str,
                     ".GetUniqueNameForOp(\"", op_info.op_name, "\");\n");
  strings::StrAppend(
      &body, "  auto builder = ::tensorflow::NodeBuilder(unique_name, \"",
      op_info.graph_op_def.name(), "\")\n");

  for (int i = start_value_index; i < end_value_index; ++i) {
    inputs.push_back(op.input(i));
  }

  auto shapes = ShapeN(scope, inputs);
  const auto unique_name = scope.GetUniqueNameForOp("ConcatOffset");
  auto builder =
      ::tensorflow::NodeBuilder(unique_name, "ConcatOffset")
          .Input(::tensorflow::ops::AsNodeOut(scope, op.input(dim_index)))