[CI] Try introducing isort. (#3495)

vllm/entrypoints/openai/serving_engine.py

@@ -3,16 +3,16 @@ import json
 from dataclasses import dataclass
 from http import HTTPStatus
 from typing import Dict, List, Optional, Union
-from vllm.logger import init_logger
-from vllm.transformers_utils.tokenizer import get_tokenizer
+
 from vllm.engine.async_llm_engine import AsyncLLMEngine
-from vllm.entrypoints.openai.protocol import (CompletionRequest,
-                                              ChatCompletionRequest,
-                                              ErrorResponse, LogProbs,
-                                              ModelCard, ModelList,
+from vllm.entrypoints.openai.protocol import (ChatCompletionRequest,
+                                              CompletionRequest, ErrorResponse,
+                                              LogProbs, ModelCard, ModelList,
                                               ModelPermission)
+from vllm.logger import init_logger
 from vllm.lora.request import LoRARequest
 from vllm.sequence import Logprob
+from vllm.transformers_utils.tokenizer import get_tokenizer
 
 logger = init_logger(__name__)