class_docstr: MNISTDigitClassifier handler class. This handler extends class ImageClassifier from image_classifier.py, a
  default handler. This handler takes image as a tensor and returns the number in that image.
  
  Here method postprocess() has been overridden while others are reused from parent class.
code: def __init__(self):
      super(MNISTDigitClassifier, self).__init__()
      self.profiler_args = {
          "activities": [ProfilerActivity.CPU],
          "record_shapes": True,
      }
  
file_path: serve/examples/image_classifier/mnist/torchdata/mnist_handler.py
imports: import numpy
  import torch
  from torch.profiler import ProfilerActivity
  from torchvision import transforms
  from ts.torch_handler.image_classifier import ImageClassifier
label_desc: Use image node_id 1 to create a new MNISTDigitClassifier object from inherited base classes: ImageClassifier with example: obj = MNISTDigitClassifier()