code: def epoch_size(self, *args, **kwargs):
      return (
          self.data_set_len
          if self.data_set_len is not None
          else len(self.loader.data_set)
      )
  
imports: import argparse
  import cv2
  import numpy
  import nvidia.dali
  import nvidia.dali.types
  import os
label_desc: Use image node_id 2 for calling the ExternalSourcePipeline obj's underlying member method code with example usage: obj.epoch_size() and returns: unknown