Not converted to TensorRT model OR Issue while Optimize with TensorRT

[kvnptl]

import tensorflow.contrib.tensorrt as trt

trt_graph = trt.create_inference_graph(
    input_graph_def=frozen_graph,
    outputs=output_names,
    max_batch_size=1,
    max_workspace_size_bytes=1 << 25,
    precision_mode='FP16',
    minimum_segment_size=50
)

while running above code in Google Colab, it gives, INFO:tensorflow:Running against TensorRT version 0.0.0 And optimized TensorRT model has same size as frozen model. It seems frozen model not converted to TensorRT model.

Can someone clarify, why it is showing TensorRT version 0.0.0?