[Misc] Upgrade more code to Python 3.10 (#26463)

Signed-off-by: DarkLight1337 <tlleungac@connect.ust.hk>

tests/entrypoints/openai/test_chat.py

@@ -369,7 +369,7 @@ async def test_chat_completion_stream_options(
             assert chunk.usage is None
         else:
             assert chunk.usage is None
-            final_chunk = await stream.__anext__()
+            final_chunk = await anext(stream)
             assert final_chunk.usage is not None
             assert final_chunk.usage.prompt_tokens > 0
             assert final_chunk.usage.completion_tokens > 0

tests/entrypoints/test_context.py

@@ -10,12 +10,6 @@ from vllm.entrypoints.context import HarmonyContext, StreamingHarmonyContext
 from vllm.outputs import CompletionOutput, RequestOutput
 
 
-# Helper function for Python < 3.10 compatibility
-async def async_next(async_iterator):
-    """Compatibility function equivalent to Python 3.10's anext()."""
-    return await async_iterator.__anext__()
-
-
 def create_mock_request_output(
     prompt_token_ids=None,
     output_token_ids=None,
@@ -129,7 +123,7 @@ async def test_multi_turn_token_counting():
     )
 
     # First turn - initial prompt and response
-    mock_output1 = await async_next(mock_generator)
+    mock_output1 = await anext(mock_generator)
     context.append_output(mock_output1)
 
     # At this point, we should have 5 prompt tokens and 3 output tokens
@@ -138,7 +132,7 @@ async def test_multi_turn_token_counting():
     assert context.num_tool_output_tokens == 0
 
     # Second turn - after tool output
-    mock_output2 = await async_next(mock_generator)
+    mock_output2 = await anext(mock_generator)
     context.append_output(mock_output2)
     # Current prompt tokens (15) - last_turn_input_tokens (5) -
     # last_turn_output_tokens (3) = 7
@@ -150,7 +144,7 @@ async def test_multi_turn_token_counting():
     assert context.num_cached_tokens == 5
 
     # Third turn - final response
-    mock_output3 = await async_next(mock_generator)
+    mock_output3 = await anext(mock_generator)
     context.append_output(mock_output3)
     # Additional tool output tokens from third turn:
     # Current prompt (20) - last_turn_input_tokens (15) -

tests/utils_/test_utils.py

@@ -75,8 +75,7 @@ async def test_merge_async_iterators():
 
     for iterator in iterators:
         try:
-            # Can use anext() in python >= 3.10
-            await asyncio.wait_for(iterator.__anext__(), 1)
+            await asyncio.wait_for(anext(iterator), 1)
         except StopAsyncIteration:
             # All iterators should be cancelled and print this message.
             print("Iterator was cancelled normally")

tests/v1/entrypoints/openai/test_completion.py

@@ -420,7 +420,7 @@ async def test_completion_stream_options(client: openai.AsyncOpenAI, model_name:
             assert chunk.usage is None
         else:
             assert chunk.usage is None
-            final_chunk = await stream.__anext__()
+            final_chunk = await anext(stream)
             assert final_chunk.usage is not None
             assert final_chunk.usage.prompt_tokens > 0
             assert final_chunk.usage.completion_tokens > 0
@@ -450,7 +450,7 @@ async def test_completion_stream_options(client: openai.AsyncOpenAI, model_name:
             chunk.usage.prompt_tokens + chunk.usage.completion_tokens
         )
         if chunk.choices[0].finish_reason is not None:
-            final_chunk = await stream.__anext__()
+            final_chunk = await anext(stream)
             assert final_chunk.usage is not None
             assert final_chunk.usage.prompt_tokens > 0
             assert final_chunk.usage.completion_tokens > 0

vllm/benchmarks/serve.py

@@ -18,6 +18,7 @@ On the client side, run:
 
 import argparse
 import asyncio
+import contextlib
 import gc
 import importlib.util
 import json
@@ -605,17 +606,13 @@ async def benchmark(
 
     pbar = None if disable_tqdm else tqdm(total=len(input_requests))
 
-    # This can be used once the minimum Python version is 3.10 or higher,
-    # and it will simplify the code in limited_request_func.
-    #    semaphore = (asyncio.Semaphore(max_concurrency)
-    #                 if max_concurrency else contextlib.nullcontext())
-    semaphore = asyncio.Semaphore(max_concurrency) if max_concurrency else None
+    semaphore = (
+        asyncio.Semaphore(max_concurrency)
+        if max_concurrency
+        else contextlib.nullcontext()
+    )
 
     async def limited_request_func(request_func_input, session, pbar):
-        if semaphore is None:
-            return await request_func(
-                request_func_input=request_func_input, session=session, pbar=pbar
-            )
         async with semaphore:
             return await request_func(
                 request_func_input=request_func_input, session=session, pbar=pbar

vllm/utils/__init__.py

@@ -469,11 +469,6 @@ def make_async(
     return _async_wrapper
 
 
-def _next_task(iterator: AsyncGenerator[T, None], loop: AbstractEventLoop) -> Task:
-    # Can use anext() in python >= 3.10
-    return loop.create_task(iterator.__anext__())  # type: ignore[arg-type]
-
-
 async def merge_async_iterators(
     *iterators: AsyncGenerator[T, None],
 ) -> AsyncGenerator[tuple[int, T], None]:
@@ -491,7 +486,7 @@ async def merge_async_iterators(
 
     loop = asyncio.get_running_loop()
 
-    awaits = {_next_task(pair[1], loop): pair for pair in enumerate(iterators)}
+    awaits = {loop.create_task(anext(it)): (i, it) for i, it in enumerate(iterators)}
     try:
         while awaits:
             done, _ = await asyncio.wait(awaits.keys(), return_when=FIRST_COMPLETED)
@@ -500,7 +495,7 @@ async def merge_async_iterators(
                 try:
                     item = await d
                     i, it = pair
-                    awaits[_next_task(it, loop)] = pair
+                    awaits[loop.create_task(anext(it))] = pair
                     yield i, item
                 except StopAsyncIteration:
                     pass

vllm/v1/serial_utils.py

@@ -290,9 +290,7 @@ class MsgpackDecoder:
             _log_insecure_serialization_warning()
 
     def decode(self, bufs: Union[bytestr, Sequence[bytestr]]) -> Any:
-        if isinstance(bufs, (bytes, bytearray, memoryview, zmq.Frame)):
-            # TODO - This check can become `isinstance(bufs, bytestr)`
-            # as of Python 3.10.
+        if isinstance(bufs, bytestr):  # type: ignore
             return self.decoder.decode(bufs)
 
         self.aux_buffers = bufs