code: def test_post_call_rule():
      try:
          litellm.pre_call_rules = []
          litellm.post_call_rules = [my_post_call_rule]
          ### completion
          response = completion(
              model="gpt-3.5-turbo",
              messages=[{"role": "user", "content": "say sorry"}],
              max_tokens=2,
          )
          pytest.fail(f"Completion call should have been failed. ")
      except Exception as e:
          print("Got exception", e)
          print(type(e))
          print(vars(e))
          assert (
              e.message
              == "This violates LiteLLM Proxy Rules. Response too short"
          )
          pass
      # print(f"MAKING ACOMPLETION CALL")
      # litellm.set_verbose = True
      ### async completion
      # async def test_async_response():
      #     messages=[{"role": "user", "content": "say sorry"}]
      #     try:
      #         response = await acompletion(model="gpt-3.5-turbo", messages=messages)
      #         pytest.fail(f"acompletion call should have been failed.")
      #     except Exception as e:
      #         pass
      # asyncio.run(test_async_response())
      litellm.pre_call_rules = []
      litellm.post_call_rules = []
  
file_path: litellm/litellm/tests/test_rules.py
imports: import sys, os, time
  import traceback, asyncio
  import pytest
  import litellm
  from litellm import completion, acompletion
label_desc: Use image node_id 4 for calling a global function with example usage: test_post_call_rule() without return types