class_docstr: Tests are in order with the design doc.
code: def test_stream_prompt_feedback_blocked(self):
      chunks = [
          glm.GenerateContentResponse(
              {
                  "prompt_feedback": {"block_reason": "SAFETY"},
              }
          )
      ]
      self.responses["stream_generate_content"] = [
          (chunk for chunk in chunks)
      ]
  
      model = generative_models.GenerativeModel("gemini-m")
      response = model.generate_content("Bad stuff!", stream=True)
  
      self.assertEqual(
          response.prompt_feedback.block_reason,
          glm.GenerateContentResponse.PromptFeedback.BlockReason.SAFETY,
      )
  
      with self.assertRaises(generation_types.BlockedPromptException):
          for chunk in response:
              pass
  
imports: import collections
  from collections.abc import Iterable
  import copy
  import pathlib
  import unittest.mock
  from absl.testing import absltest
  from absl.testing import parameterized
  import google.ai.generativelanguage
  from google.generativeai import client
  from google.generativeai import generative_models
  from google.generativeai.types import content_types
  from google.generativeai.types import generation_types
  import PIL.Image
label_desc: Use image node_id 8 for calling the CUJTests obj's underlying member method code with example usage: obj.test_stream_prompt_feedback_blocked() without return types