code: def predict(self, test_set, return_proba=False):
      raise NotImplementedError()
  
imports: import unittest
  import pytest
  import torch
  import numpy
  from small_text.integrations.pytorch.exceptions import PytorchNotFoundError
label_desc: Use image node_id 4 for calling the PytorchClassifierImplementation obj's underlying member method code with example usage: obj.predict(test_set, return_proba) without return types