code: def testGetNodeMapEmpty(self):
      meta_graph_def = meta_graph_pb2.MetaGraphDef()
      self.assertDictEqual(
          {},
          graph_ref.get_node_map(
              meta_graph_def, "my_collection", ["fruits"]
          ),
      )
  
file_path: model-analysis/tensorflow_model_analysis/eval_saved_model/graph_ref_test.py
imports: import tensorflow
  from tensorflow_model_analysis.eval_saved_model import encoding
  from tensorflow_model_analysis.eval_saved_model import graph_ref
  from tensorflow.core.protobuf import meta_graph_pb2
label_desc: Use image node_id 4 for calling the GraphRefTest obj's underlying member method code with example usage: obj.testGetNodeMapEmpty() without return types