from contextlib import asynccontextmanager as asynccontextmanager
from typing import TypeVar

import anyio.to_thread
from anyio import CapacityLimiter
from starlette.concurrency import iterate_in_threadpool as iterate_in_threadpool  # noqa
from starlette.concurrency import run_in_threadpool as run_in_threadpool  # noqa
from starlette.concurrency import (  # noqa
    run_until_first_complete as run_until_first_complete,
)

import inspect
import sys
from collections.abc import AsyncGenerator, Generator
from functools import wraps

import pytest
from fastapi import Depends, FastAPI
from fastapi.concurrency import iterate_in_threadpool, run_in_threadpool
from fastapi.testclient import TestClient

if sys.version_info >= (3, 13):  # pragma: no cover
    from inspect import iscoroutinefunction
else:  # pragma: no cover
    from asyncio import iscoroutinefunction

    * It's now possible to use the low level utility `iterate_in_threadpool` from `starlette.concurrency` (for advanced scenarios).
    * PR [#243](https://github.com/tiangolo/fastapi/pull/243).