如何在Tensorflow中从冻结的模型( pb文件)中找到output_node_names？

import tensorflow as tf

model_path = 'path/to/frozen_model.pb'
with tf.gfile.GFile(model_path, 'rb') as f:
    graph_def = tf.GraphDef()
    graph_def.ParseFromString(f.read())

node_names = [node.name for node in graph_def.node]

output_node_names = []
for node in graph_def.node:
    if 'output' in node.name.lower():
        output_node_names.append(node.name)