Starlette （和 **FastAPI**） 是基於 <a href="https://anyio.readthedocs.io/en/stable/" class="external-link" target="_blank">AnyIO</a> 實作的，這使得它們與 Python 標準函式庫相容 <a href="https://docs.python.org/3/library/asyncio-task.html" class="external-link" target="_blank">asyncio</a> 和 <a href="https://trio.readthedocs.io/en/stable/" class="external-link" target="_blank">Trio</a>。

from copy import copy, deepcopy
from dataclasses import dataclass
from typing import (
    Annotated,
    Any,
    Callable,
    ForwardRef,
    Optional,
    Union,
    cast,
)

import anyio
from fastapi import params
from fastapi._compat import (
    ModelField,
    RequiredParam,
    Undefined,
    _regenerate_error_with_loc,
    copy_field_info,
    create_body_model,
    evaluate_forwardref,

This release adds support for [Trio](https://trio.readthedocs.io/en/stable/). ✨

It upgrades the version of Starlette to `0.15.0`, now based on [AnyIO](https://anyio.readthedocs.io/en/stable/), and the internal async components in **FastAPI** are now based on AnyIO as well, making it compatible with both **asyncio** and **Trio**.

                # except HTTPException inside a dependency with yield.
                # This needs to happen after user middlewares because those create a
                # new contextvars context copy by using a new AnyIO task group.
                # This AsyncExitStack preserves the context for contextvars, not
                # strictly necessary for closing files but it was one of the original
                # intentions.