code: def test_default_base_api(tmp_path):
      route_no_base = {
          "routes": [
              {
                  "name": "chat-gpt4",
                  "route_type": "llm/v1/chat",
                  "model": {
                      "name": "gpt-4",
                      "provider": "openai",
                      "config": {"openai_api_key": "sk-openai"},
                  },
              },
          ]
      }
      conf_path = tmp_path.joinpath("config.yaml")
      conf_path.write_text(yaml.safe_dump(route_no_base))
      loaded_conf = _load_route_config(conf_path)
  
      assert (
          loaded_conf.routes[0].model.config.openai_api_base
          == "https://api.openai.com/v1"
      )
  
file_path: mlflow/tests/gateway/test_gateway_config_parsing.py
imports: import re
  import warnings
  import pytest
  import yaml
  from mlflow.exceptions import MlflowException
  from mlflow.gateway.config import AnthropicConfig, OpenAIConfig, RouteConfig, _load_route_config, _resolve_api_key_from_input, _save_route_config
  from mlflow.gateway.utils import assemble_uri_path
label_desc: Use image node_id 11 for calling a global function with example usage: test_default_base_api(tmp_path) without return types