code: def test_fit_with_differentiable_head(self):
      ds = random_text_dataset(10, multi_label=self.multi_label)
      setfit_model_args = SetFitModelArguments(
          "sentence-transformers/all-MiniLM-L6-v2"
      )
      num_classes = 5
  
      clf = SetFitClassification(
          setfit_model_args,
          num_classes,
          multi_label=self.multi_label,
          use_differentiable_head=self.use_differentiable_head,
      )
      with self.assertRaises(NotImplementedError):
          clf.fit(ds)
  
imports: import unittest
  import pytest
  from unittest.mock import patch
  from small_text.integrations.pytorch.exceptions import PytorchNotFoundError
label_desc: Use image node_id 2 for calling the TestSetFitClassificationDifferentiableMultiLabel obj's underlying member method code with example usage: obj.test_fit_with_differentiable_head() without return types