// parameter of TF_GraphImportGraphDef(). `oper_name` is copied and has no
// lifetime requirements.
TF_CAPI_EXPORT extern void TF_ImportGraphDefOptionsAddReturnOperation(
    TF_ImportGraphDefOptions* opts, const char* oper_name);

// Returns the number of return operations added via
// TF_ImportGraphDefOptionsAddReturnOperation().
TF_CAPI_EXPORT extern int TF_ImportGraphDefOptionsNumReturnOperations(
    const TF_ImportGraphDefOptions* opts);

  TF_ImportGraphDefOptionsAddReturnOutput(opts, "feed", 0);
  TF_ImportGraphDefOptionsAddReturnOutput(opts, "scalar", 0);
  EXPECT_EQ(2, TF_ImportGraphDefOptionsNumReturnOutputs(opts));
  TF_ImportGraphDefOptionsAddReturnOperation(opts, "scalar");
  EXPECT_EQ(1, TF_ImportGraphDefOptionsNumReturnOperations(opts));
  tensorflow::GraphDef graph_def_proto;
  ASSERT_TRUE(tensorflow::ParseProtoUnlimited(&graph_def_proto, graph_def->data,