code: def test_vertex_ai():
      import random
  
      load_vertex_ai_credentials()
      test_models = (
          litellm.vertex_chat_models
          + litellm.vertex_code_chat_models
          + litellm.vertex_text_models
          + litellm.vertex_code_text_models
      )
      litellm.set_verbose = False
      litellm.vertex_project = "reliablekeys"
  
      test_models = random.sample(test_models, 1)
      # test_models += litellm.vertex_language_models  # always test gemini-pro
      test_models = (
          litellm.vertex_language_models
      )  # always test gemini-pro
      for model in test_models:
          try:
              if model in [
                  "code-gecko",
                  "code-gecko@001",
                  "code-gecko@002",
                  "code-gecko@latest",
                  "code-bison@001",
                  "text-bison@001",
              ]:
                  # our account does not have access to this model
                  continue
              print("making request", model)
              response = completion(
                  model=model,
                  messages=[{"role": "user", "content": "hi"}],
                  temperature=0.7,
              )
              print("\nModel Response", response)
              print(response)
              assert type(response.choices[0].message.content) == str
              assert len(response.choices[0].message.content) > 1
          except Exception as e:
              pytest.fail(f"Error occurred: {e}")
  
file_path: litellm/litellm/tests/test_amazing_vertex_completion.py
imports: import sys, os
  import traceback
  from dotenv import load_dotenv
  import os, io
  import pytest, asyncio
  import litellm
  from litellm import embedding, completion, completion_cost, Timeout, acompletion
  from litellm import RateLimitError
  import json
  import os
  import tempfile
label_desc: Use image node_id 2 for calling a global function with example usage: test_vertex_ai() without return types