output layers' name in C api Tensorflow

Question

I am trying to load a pre-trained Tensorflow model in C api (for example - faster_rcnn/resnet101_v1_640x640). I loaded it using:

TF_LoadSessionFromSavedModel(session_options, run_options, name, &tag, 1, graph, meta_graph, status);

I printed out all the layers in order to see the names of the output layers, and they are weird, here are some of them:

serving_default_input_tensor

StatefulPartitionedCall

saver_filename

StatefulPartitionedCall_1

StatefulPartitionedCall_2

What do these layers mean? Where is the "num_detections" output (it is defined in the model page...)

Thank you!