docstr: Test functionality for degenerate tasks.
code: def test_offensive_degenerate_case(self):
      """
      Test functionality for degenerate tasks.
      """
      from parlai.scripts.detect_offensive_language import (
          DetectOffensive,
      )
  
      report = DetectOffensive.main(
          task="integration_tests:overfit",
          safety="all",
          mutators="degenerate",
      )
      assert report["classifier_offenses%"] == 0
      assert report["exs"] == 4
  
imports: import os
  import unittest
  from parlai.core.message import Message
  from parlai.core.mutators import MessageMutator, register_mutator
  import parlai.utils.testing
label_desc: Use image node_id 2 for calling the TestDetectOffensive obj's underlying member method code with example usage: obj.test_offensive_degenerate_case() without return types