tornado/platform/asyncio.py

asyncio.py

import concurrent.futures
import functools

from threading import get_ident
from tornado.gen import convert_yielded
from tornado.ioloop import IOLoop, _Selectable

import asyncio

# Start of fix for Windows
import sys

if sys.platform == 'win32':
    asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())
# End of fix

import typing
from typing import Any, TypeVar, Awaitable, Callable, Union, Optional

if typing.TYPE_CHECKING:
    from typing import Set, Dict, Tuple  # noqa: F401

_T = TypeVar("_T")