// Make a placeholder operation.
  TF_Operation* feed = Placeholder(graph, s);
  ASSERT_EQ(TF_OK, TF_GetCode(s)) << TF_Message(s);

  // Test TF_Operation*() query functions.
  EXPECT_EQ(string("feed"), string(TF_OperationName(feed)));
  EXPECT_EQ(string("Placeholder"), string(TF_OperationOpType(feed)));
  EXPECT_EQ(string(""), string(TF_OperationDevice(feed)));
  EXPECT_EQ(1, TF_OperationNumOutputs(feed));

    TF_OperationDescription* desc, TF_Status* status);

// TF_Operation functions.  Operations are immutable once created, so
// these are all query functions.

TF_CAPI_EXPORT extern const char* TF_OperationName(TF_Operation* oper);
TF_CAPI_EXPORT extern const char* TF_OperationOpType(TF_Operation* oper);
TF_CAPI_EXPORT extern const char* TF_OperationDevice(TF_Operation* oper);