code: def completions_response():
      return {
          "generated_text": "this is a test response",
          "details": {
              "finish_reason": "length",
              "generated_tokens": 5,
              "seed": 0,
              "prefill": [
                  {"text": "This"},
                  {"text": "is"},
                  {"text": "a"},
                  {"text": "test"},
              ],
          },
      }
  
file_path: mlflow/tests/gateway/providers/test_huggingface.py
imports: from unittest import mock
  import pytest
  from aiohttp import ClientTimeout
  from fastapi import HTTPException
  from fastapi.encoders import jsonable_encoder
  from mlflow.gateway.config import RouteConfig
  from mlflow.gateway.constants import MLFLOW_GATEWAY_ROUTE_TIMEOUT_SECONDS
  from mlflow.gateway.providers.huggingface import HFTextGenerationInferenceServerProvider
  from mlflow.gateway.schemas import chat, completions, embeddings
  from tests.gateway.tools import MockAsyncResponse
label_desc: Use image node_id 4 for calling a global function with example usage: completions_response() and returns: dict