code: def test_model_group_aliases():
      try:
          litellm.set_verbose = False
          model_list = [
              {
                  "model_name": "gpt-3.5-turbo",
                  "litellm_params": {
                      "model": "gpt-3.5-turbo-0613",
                      "api_key": os.getenv("OPENAI_API_KEY"),
                      "tpm": 1,
                  },
              },
              {
                  "model_name": "gpt-3.5-turbo",
                  "litellm_params": {
                      "model": "azure/chatgpt-v-2",
                      "api_key": os.getenv("AZURE_API_KEY"),
                      "api_base": os.getenv("AZURE_API_BASE"),
                      "api_version": os.getenv("AZURE_API_VERSION"),
                      "tpm": 99,
                  },
              },
              {
                  "model_name": "claude-1",
                  "litellm_params": {
                      "model": "bedrock/claude1.2",
                      "tpm": 1,
                  },
              },
          ]
          router = Router(
              model_list=model_list,
              model_group_alias={
                  "gpt-4": "gpt-3.5-turbo"
              },  # gpt-4 requests sent to gpt-3.5-turbo
          )
  
          # test that gpt-4 requests are sent to gpt-3.5-turbo
          for _ in range(20):
              selected_model = router.get_available_deployment("gpt-4")
              print("\n selected model", selected_model)
              selected_model_name = selected_model.get("model_name")
              if selected_model_name != "gpt-3.5-turbo":
                  pytest.fail(
                      f"Selected model {selected_model_name} is not gpt-3.5-turbo"
                  )
  
          # test that
          # call get_available_deployment 1k times, it should pick azure/chatgpt-v-2 about 90% of the time
          selection_counts = defaultdict(int)
          for _ in range(1000):
              selected_model = router.get_available_deployment(
                  "gpt-3.5-turbo"
              )
              selected_model_id = selected_model["litellm_params"][
                  "model"
              ]
              selected_model_name = selected_model_id
              selection_counts[selected_model_name] += 1
          print(selection_counts)
  
          total_requests = sum(selection_counts.values())
  
          # Assert that 'azure/chatgpt-v-2' has about 90% of the total requests
          assert (
              selection_counts["azure/chatgpt-v-2"] / total_requests
              > 0.89
          ), f"Assertion failed: 'azure/chatgpt-v-2' does not have about 90% of the total requests in the weighted load balancer. Selection counts {selection_counts}"
  
          router.reset()
      except Exception as e:
          traceback.print_exc()
          pytest.fail(f"Error occurred: {e}")
  
file_path: litellm/litellm/tests/test_router_get_deployments.py
imports: import sys, os, time
  import traceback, asyncio
  import pytest
  import litellm
  from litellm import Router
  from concurrent.futures import ThreadPoolExecutor
  from collections import defaultdict
  from dotenv import load_dotenv
label_desc: Use image node_id 6 for calling a global function with example usage: test_model_group_aliases() without return types