code: def tearDown(self):
      pass
  
file_path: image-super-resolution/tests/utils/test_metrics.py
imports: import unittest
  import numpy
  import tensorflow.keras.backend
  from ISR.utils.metrics import PSNR
label_desc: Use image node_id 2 for calling the MetricsClassTest obj's underlying member method code with example usage: obj.tearDown() without return types