code: def test_custom_auth(client):
      try:
          # Your test data
          test_data = {
              "model": "openai-model",
              "messages": [
                  {"role": "user", "content": "hi"},
              ],
              "max_tokens": 10,
          }
          # Your bearer token
          token = os.getenv("PROXY_MASTER_KEY")
  
          headers = {"Authorization": f"Bearer {token}"}
          response = client.post(
              "/chat/completions", json=test_data, headers=headers
          )
          print(f"response: {response.text}")
          assert response.status_code == 401
          result = response.json()
          print(f"Received response: {result}")
      except Exception as e:
          pytest.fail("LiteLLM Proxy test failed. Exception", e)
  
file_path: litellm/litellm/tests/test_proxy_custom_auth.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
  from litellm import RateLimitError
  from fastapi.testclient import TestClient
  from fastapi import FastAPI
  from litellm.proxy.proxy_server import router, save_worker_config, initialize, ProxyConfig
label_desc: Use image node_id 2 for calling a global function with example usage: test_custom_auth(client) without return types