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diff --git a/.venv/lib/python3.12/site-packages/websockets/legacy/protocol.py b/.venv/lib/python3.12/site-packages/websockets/legacy/protocol.py
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+from __future__ import annotations
+
+import asyncio
+import codecs
+import collections
+import logging
+import random
+import ssl
+import struct
+import sys
+import time
+import traceback
+import uuid
+import warnings
+from collections.abc import AsyncIterable, AsyncIterator, Awaitable, Iterable, Mapping
+from typing import Any, Callable, Deque, cast
+
+from ..asyncio.compatibility import asyncio_timeout
+from ..datastructures import Headers
+from ..exceptions import (
+    ConnectionClosed,
+    ConnectionClosedError,
+    ConnectionClosedOK,
+    InvalidState,
+    PayloadTooBig,
+    ProtocolError,
+)
+from ..extensions import Extension
+from ..frames import (
+    OK_CLOSE_CODES,
+    OP_BINARY,
+    OP_CLOSE,
+    OP_CONT,
+    OP_PING,
+    OP_PONG,
+    OP_TEXT,
+    Close,
+    CloseCode,
+    Opcode,
+)
+from ..protocol import State
+from ..typing import Data, LoggerLike, Subprotocol
+from .framing import Frame, prepare_ctrl, prepare_data
+
+
+__all__ = ["WebSocketCommonProtocol"]
+
+
+# In order to ensure consistency, the code always checks the current value of
+# WebSocketCommonProtocol.state before assigning a new value and never yields
+# between the check and the assignment.
+
+
+class WebSocketCommonProtocol(asyncio.Protocol):
+    """
+    WebSocket connection.
+
+    :class:`WebSocketCommonProtocol` provides APIs shared between WebSocket
+    servers and clients. You shouldn't use it directly. Instead, use
+    :class:`~websockets.legacy.client.WebSocketClientProtocol` or
+    :class:`~websockets.legacy.server.WebSocketServerProtocol`.
+
+    This documentation focuses on low-level details that aren't covered in the
+    documentation of :class:`~websockets.legacy.client.WebSocketClientProtocol`
+    and :class:`~websockets.legacy.server.WebSocketServerProtocol` for the sake
+    of simplicity.
+
+    Once the connection is open, a Ping_ frame is sent every ``ping_interval``
+    seconds. This serves as a keepalive. It helps keeping the connection open,
+    especially in the presence of proxies with short timeouts on inactive
+    connections. Set ``ping_interval`` to :obj:`None` to disable this behavior.
+
+    .. _Ping: https://datatracker.ietf.org/doc/html/rfc6455#section-5.5.2
+
+    If the corresponding Pong_ frame isn't received within ``ping_timeout``
+    seconds, the connection is considered unusable and is closed with code 1011.
+    This ensures that the remote endpoint remains responsive. Set
+    ``ping_timeout`` to :obj:`None` to disable this behavior.
+
+    .. _Pong: https://datatracker.ietf.org/doc/html/rfc6455#section-5.5.3
+
+    See the discussion of :doc:`keepalive <../../topics/keepalive>` for details.
+
+    The ``close_timeout`` parameter defines a maximum wait time for completing
+    the closing handshake and terminating the TCP connection. For legacy
+    reasons, :meth:`close` completes in at most ``5 * close_timeout`` seconds
+    for clients and ``4 * close_timeout`` for servers.
+
+    ``close_timeout`` is a parameter of the protocol because websockets usually
+    calls :meth:`close` implicitly upon exit:
+
+    * on the client side, when using :func:`~websockets.legacy.client.connect`
+      as a context manager;
+    * on the server side, when the connection handler terminates.
+
+    To apply a timeout to any other API, wrap it in :func:`~asyncio.timeout` or
+    :func:`~asyncio.wait_for`.
+
+    The ``max_size`` parameter enforces the maximum size for incoming messages
+    in bytes. The default value is 1 MiB. If a larger message is received,
+    :meth:`recv` will raise :exc:`~websockets.exceptions.ConnectionClosedError`
+    and the connection will be closed with code 1009.
+
+    The ``max_queue`` parameter sets the maximum length of the queue that
+    holds incoming messages. The default value is ``32``. Messages are added
+    to an in-memory queue when they're received; then :meth:`recv` pops from
+    that queue. In order to prevent excessive memory consumption when
+    messages are received faster than they can be processed, the queue must
+    be bounded. If the queue fills up, the protocol stops processing incoming
+    data until :meth:`recv` is called. In this situation, various receive
+    buffers (at least in :mod:`asyncio` and in the OS) will fill up, then the
+    TCP receive window will shrink, slowing down transmission to avoid packet
+    loss.
+
+    Since Python can use up to 4 bytes of memory to represent a single
+    character, each connection may use up to ``4 * max_size * max_queue``
+    bytes of memory to store incoming messages. By default, this is 128 MiB.
+    You may want to lower the limits, depending on your application's
+    requirements.
+
+    The ``read_limit`` argument sets the high-water limit of the buffer for
+    incoming bytes. The low-water limit is half the high-water limit. The
+    default value is 64 KiB, half of asyncio's default (based on the current
+    implementation of :class:`~asyncio.StreamReader`).
+
+    The ``write_limit`` argument sets the high-water limit of the buffer for
+    outgoing bytes. The low-water limit is a quarter of the high-water limit.
+    The default value is 64 KiB, equal to asyncio's default (based on the
+    current implementation of ``FlowControlMixin``).
+
+    See the discussion of :doc:`memory usage <../../topics/memory>` for details.
+
+    Args:
+        logger: Logger for this server.
+            It defaults to ``logging.getLogger("websockets.protocol")``.
+            See the :doc:`logging guide <../../topics/logging>` for details.
+        ping_interval: Interval between keepalive pings in seconds.
+            :obj:`None` disables keepalive.
+        ping_timeout: Timeout for keepalive pings in seconds.
+            :obj:`None` disables timeouts.
+        close_timeout: Timeout for closing the connection in seconds.
+            For legacy reasons, the actual timeout is 4 or 5 times larger.
+        max_size: Maximum size of incoming messages in bytes.
+            :obj:`None` disables the limit.
+        max_queue: Maximum number of incoming messages in receive buffer.
+            :obj:`None` disables the limit.
+        read_limit: High-water mark of read buffer in bytes.
+        write_limit: High-water mark of write buffer in bytes.
+
+    """
+
+    # There are only two differences between the client-side and server-side
+    # behavior: masking the payload and closing the underlying TCP connection.
+    # Set is_client = True/False and side = "client"/"server" to pick a side.
+    is_client: bool
+    side: str = "undefined"
+
+    def __init__(
+        self,
+        *,
+        logger: LoggerLike | None = None,
+        ping_interval: float | None = 20,
+        ping_timeout: float | None = 20,
+        close_timeout: float | None = None,
+        max_size: int | None = 2**20,
+        max_queue: int | None = 2**5,
+        read_limit: int = 2**16,
+        write_limit: int = 2**16,
+        # The following arguments are kept only for backwards compatibility.
+        host: str | None = None,
+        port: int | None = None,
+        secure: bool | None = None,
+        legacy_recv: bool = False,
+        loop: asyncio.AbstractEventLoop | None = None,
+        timeout: float | None = None,
+    ) -> None:
+        if legacy_recv:  # pragma: no cover
+            warnings.warn("legacy_recv is deprecated", DeprecationWarning)
+
+        # Backwards compatibility: close_timeout used to be called timeout.
+        if timeout is None:
+            timeout = 10
+        else:
+            warnings.warn("rename timeout to close_timeout", DeprecationWarning)
+        # If both are specified, timeout is ignored.
+        if close_timeout is None:
+            close_timeout = timeout
+
+        # Backwards compatibility: the loop parameter used to be supported.
+        if loop is None:
+            loop = asyncio.get_event_loop()
+        else:
+            warnings.warn("remove loop argument", DeprecationWarning)
+
+        self.ping_interval = ping_interval
+        self.ping_timeout = ping_timeout
+        self.close_timeout = close_timeout
+        self.max_size = max_size
+        self.max_queue = max_queue
+        self.read_limit = read_limit
+        self.write_limit = write_limit
+
+        # Unique identifier. For logs.
+        self.id: uuid.UUID = uuid.uuid4()
+        """Unique identifier of the connection. Useful in logs."""
+
+        # Logger or LoggerAdapter for this connection.
+        if logger is None:
+            logger = logging.getLogger("websockets.protocol")
+        self.logger: LoggerLike = logging.LoggerAdapter(logger, {"websocket": self})
+        """Logger for this connection."""
+
+        # Track if DEBUG is enabled. Shortcut logging calls if it isn't.
+        self.debug = logger.isEnabledFor(logging.DEBUG)
+
+        self.loop = loop
+
+        self._host = host
+        self._port = port
+        self._secure = secure
+        self.legacy_recv = legacy_recv
+
+        # Configure read buffer limits. The high-water limit is defined by
+        # ``self.read_limit``. The ``limit`` argument controls the line length
+        # limit and half the buffer limit of :class:`~asyncio.StreamReader`.
+        # That's why it must be set to half of ``self.read_limit``.
+        self.reader = asyncio.StreamReader(limit=read_limit // 2, loop=loop)
+
+        # Copied from asyncio.FlowControlMixin
+        self._paused = False
+        self._drain_waiter: asyncio.Future[None] | None = None
+
+        self._drain_lock = asyncio.Lock()
+
+        # This class implements the data transfer and closing handshake, which
+        # are shared between the client-side and the server-side.
+        # Subclasses implement the opening handshake and, on success, execute
+        # :meth:`connection_open` to change the state to OPEN.
+        self.state = State.CONNECTING
+        if self.debug:
+            self.logger.debug("= connection is CONNECTING")
+
+        # HTTP protocol parameters.
+        self.path: str
+        """Path of the opening handshake request."""
+        self.request_headers: Headers
+        """Opening handshake request headers."""
+        self.response_headers: Headers
+        """Opening handshake response headers."""
+
+        # WebSocket protocol parameters.
+        self.extensions: list[Extension] = []
+        self.subprotocol: Subprotocol | None = None
+        """Subprotocol, if one was negotiated."""
+
+        # Close code and reason, set when a close frame is sent or received.
+        self.close_rcvd: Close | None = None
+        self.close_sent: Close | None = None
+        self.close_rcvd_then_sent: bool | None = None
+
+        # Completed when the connection state becomes CLOSED. Translates the
+        # :meth:`connection_lost` callback to a :class:`~asyncio.Future`
+        # that can be awaited. (Other :class:`~asyncio.Protocol` callbacks are
+        # translated by ``self.stream_reader``).
+        self.connection_lost_waiter: asyncio.Future[None] = loop.create_future()
+
+        # Queue of received messages.
+        self.messages: Deque[Data] = collections.deque()
+        self._pop_message_waiter: asyncio.Future[None] | None = None
+        self._put_message_waiter: asyncio.Future[None] | None = None
+
+        # Protect sending fragmented messages.
+        self._fragmented_message_waiter: asyncio.Future[None] | None = None
+
+        # Mapping of ping IDs to pong waiters, in chronological order.
+        self.pings: dict[bytes, tuple[asyncio.Future[float], float]] = {}
+
+        self.latency: float = 0
+        """
+        Latency of the connection, in seconds.
+
+        Latency is defined as the round-trip time of the connection. It is
+        measured by sending a Ping frame and waiting for a matching Pong frame.
+        Before the first measurement, :attr:`latency` is ``0``.
+
+        By default, websockets enables a :ref:`keepalive <keepalive>` mechanism
+        that sends Ping frames automatically at regular intervals. You can also
+        send Ping frames and measure latency with :meth:`ping`.
+        """
+
+        # Task running the data transfer.
+        self.transfer_data_task: asyncio.Task[None]
+
+        # Exception that occurred during data transfer, if any.
+        self.transfer_data_exc: BaseException | None = None
+
+        # Task sending keepalive pings.
+        self.keepalive_ping_task: asyncio.Task[None]
+
+        # Task closing the TCP connection.
+        self.close_connection_task: asyncio.Task[None]
+
+    # Copied from asyncio.FlowControlMixin
+    async def _drain_helper(self) -> None:  # pragma: no cover
+        if self.connection_lost_waiter.done():
+            raise ConnectionResetError("Connection lost")
+        if not self._paused:
+            return
+        waiter = self._drain_waiter
+        assert waiter is None or waiter.cancelled()
+        waiter = self.loop.create_future()
+        self._drain_waiter = waiter
+        await waiter
+
+    # Copied from asyncio.StreamWriter
+    async def _drain(self) -> None:  # pragma: no cover
+        if self.reader is not None:
+            exc = self.reader.exception()
+            if exc is not None:
+                raise exc
+        if self.transport is not None:
+            if self.transport.is_closing():
+                # Yield to the event loop so connection_lost() may be
+                # called.  Without this, _drain_helper() would return
+                # immediately, and code that calls
+                #     write(...); yield from drain()
+                # in a loop would never call connection_lost(), so it
+                # would not see an error when the socket is closed.
+                await asyncio.sleep(0)
+        await self._drain_helper()
+
+    def connection_open(self) -> None:
+        """
+        Callback when the WebSocket opening handshake completes.
+
+        Enter the OPEN state and start the data transfer phase.
+
+        """
+        # 4.1. The WebSocket Connection is Established.
+        assert self.state is State.CONNECTING
+        self.state = State.OPEN
+        if self.debug:
+            self.logger.debug("= connection is OPEN")
+        # Start the task that receives incoming WebSocket messages.
+        self.transfer_data_task = self.loop.create_task(self.transfer_data())
+        # Start the task that sends pings at regular intervals.
+        self.keepalive_ping_task = self.loop.create_task(self.keepalive_ping())
+        # Start the task that eventually closes the TCP connection.
+        self.close_connection_task = self.loop.create_task(self.close_connection())
+
+    @property
+    def host(self) -> str | None:
+        alternative = "remote_address" if self.is_client else "local_address"
+        warnings.warn(f"use {alternative}[0] instead of host", DeprecationWarning)
+        return self._host
+
+    @property
+    def port(self) -> int | None:
+        alternative = "remote_address" if self.is_client else "local_address"
+        warnings.warn(f"use {alternative}[1] instead of port", DeprecationWarning)
+        return self._port
+
+    @property
+    def secure(self) -> bool | None:
+        warnings.warn("don't use secure", DeprecationWarning)
+        return self._secure
+
+    # Public API
+
+    @property
+    def local_address(self) -> Any:
+        """
+        Local address of the connection.
+
+        For IPv4 connections, this is a ``(host, port)`` tuple.
+
+        The format of the address depends on the address family;
+        see :meth:`~socket.socket.getsockname`.
+
+        :obj:`None` if the TCP connection isn't established yet.
+
+        """
+        try:
+            transport = self.transport
+        except AttributeError:
+            return None
+        else:
+            return transport.get_extra_info("sockname")
+
+    @property
+    def remote_address(self) -> Any:
+        """
+        Remote address of the connection.
+
+        For IPv4 connections, this is a ``(host, port)`` tuple.
+
+        The format of the address depends on the address family;
+        see :meth:`~socket.socket.getpeername`.
+
+        :obj:`None` if the TCP connection isn't established yet.
+
+        """
+        try:
+            transport = self.transport
+        except AttributeError:
+            return None
+        else:
+            return transport.get_extra_info("peername")
+
+    @property
+    def open(self) -> bool:
+        """
+        :obj:`True` when the connection is open; :obj:`False` otherwise.
+
+        This attribute may be used to detect disconnections. However, this
+        approach is discouraged per the EAFP_ principle. Instead, you should
+        handle :exc:`~websockets.exceptions.ConnectionClosed` exceptions.
+
+        .. _EAFP: https://docs.python.org/3/glossary.html#term-eafp
+
+        """
+        return self.state is State.OPEN and not self.transfer_data_task.done()
+
+    @property
+    def closed(self) -> bool:
+        """
+        :obj:`True` when the connection is closed; :obj:`False` otherwise.
+
+        Be aware that both :attr:`open` and :attr:`closed` are :obj:`False`
+        during the opening and closing sequences.
+
+        """
+        return self.state is State.CLOSED
+
+    @property
+    def close_code(self) -> int | None:
+        """
+        WebSocket close code, defined in `section 7.1.5 of RFC 6455`_.
+
+        .. _section 7.1.5 of RFC 6455:
+            https://datatracker.ietf.org/doc/html/rfc6455#section-7.1.5
+
+        :obj:`None` if the connection isn't closed yet.
+
+        """
+        if self.state is not State.CLOSED:
+            return None
+        elif self.close_rcvd is None:
+            return CloseCode.ABNORMAL_CLOSURE
+        else:
+            return self.close_rcvd.code
+
+    @property
+    def close_reason(self) -> str | None:
+        """
+        WebSocket close reason, defined in `section 7.1.6 of RFC 6455`_.
+
+        .. _section 7.1.6 of RFC 6455:
+            https://datatracker.ietf.org/doc/html/rfc6455#section-7.1.6
+
+        :obj:`None` if the connection isn't closed yet.
+
+        """
+        if self.state is not State.CLOSED:
+            return None
+        elif self.close_rcvd is None:
+            return ""
+        else:
+            return self.close_rcvd.reason
+
+    async def __aiter__(self) -> AsyncIterator[Data]:
+        """
+        Iterate on incoming messages.
+
+        The iterator exits normally when the connection is closed with the close
+        code 1000 (OK) or 1001 (going away) or without a close code.
+
+        It raises a :exc:`~websockets.exceptions.ConnectionClosedError`
+        exception when the connection is closed with any other code.
+
+        """
+        try:
+            while True:
+                yield await self.recv()
+        except ConnectionClosedOK:
+            return
+
+    async def recv(self) -> Data:
+        """
+        Receive the next message.
+
+        When the connection is closed, :meth:`recv` raises
+        :exc:`~websockets.exceptions.ConnectionClosed`. Specifically, it raises
+        :exc:`~websockets.exceptions.ConnectionClosedOK` after a normal
+        connection closure and
+        :exc:`~websockets.exceptions.ConnectionClosedError` after a protocol
+        error or a network failure. This is how you detect the end of the
+        message stream.
+
+        Canceling :meth:`recv` is safe. There's no risk of losing the next
+        message. The next invocation of :meth:`recv` will return it.
+
+        This makes it possible to enforce a timeout by wrapping :meth:`recv` in
+        :func:`~asyncio.timeout` or :func:`~asyncio.wait_for`.
+
+        Returns:
+            A string (:class:`str`) for a Text_ frame. A bytestring
+            (:class:`bytes`) for a Binary_ frame.
+
+            .. _Text: https://datatracker.ietf.org/doc/html/rfc6455#section-5.6
+            .. _Binary: https://datatracker.ietf.org/doc/html/rfc6455#section-5.6
+
+        Raises:
+            ConnectionClosed: When the connection is closed.
+            RuntimeError: If two coroutines call :meth:`recv` concurrently.
+
+        """
+        if self._pop_message_waiter is not None:
+            raise RuntimeError(
+                "cannot call recv while another coroutine "
+                "is already waiting for the next message"
+            )
+
+        # Don't await self.ensure_open() here:
+        # - messages could be available in the queue even if the connection
+        #   is closed;
+        # - messages could be received before the closing frame even if the
+        #   connection is closing.
+
+        # Wait until there's a message in the queue (if necessary) or the
+        # connection is closed.
+        while len(self.messages) <= 0:
+            pop_message_waiter: asyncio.Future[None] = self.loop.create_future()
+            self._pop_message_waiter = pop_message_waiter
+            try:
+                # If asyncio.wait() is canceled, it doesn't cancel
+                # pop_message_waiter and self.transfer_data_task.
+                await asyncio.wait(
+                    [pop_message_waiter, self.transfer_data_task],
+                    return_when=asyncio.FIRST_COMPLETED,
+                )
+            finally:
+                self._pop_message_waiter = None
+
+            # If asyncio.wait(...) exited because self.transfer_data_task
+            # completed before receiving a new message, raise a suitable
+            # exception (or return None if legacy_recv is enabled).
+            if not pop_message_waiter.done():
+                if self.legacy_recv:
+                    return None  # type: ignore
+                else:
+                    # Wait until the connection is closed to raise
+                    # ConnectionClosed with the correct code and reason.
+                    await self.ensure_open()
+
+        # Pop a message from the queue.
+        message = self.messages.popleft()
+
+        # Notify transfer_data().
+        if self._put_message_waiter is not None:
+            self._put_message_waiter.set_result(None)
+            self._put_message_waiter = None
+
+        return message
+
+    async def send(
+        self,
+        message: Data | Iterable[Data] | AsyncIterable[Data],
+    ) -> None:
+        """
+        Send a message.
+
+        A string (:class:`str`) is sent as a Text_ frame. A bytestring or
+        bytes-like object (:class:`bytes`, :class:`bytearray`, or
+        :class:`memoryview`) is sent as a Binary_ frame.
+
+        .. _Text: https://datatracker.ietf.org/doc/html/rfc6455#section-5.6
+        .. _Binary: https://datatracker.ietf.org/doc/html/rfc6455#section-5.6
+
+        :meth:`send` also accepts an iterable or an asynchronous iterable of
+        strings, bytestrings, or bytes-like objects to enable fragmentation_.
+        Each item is treated as a message fragment and sent in its own frame.
+        All items must be of the same type, or else :meth:`send` will raise a
+        :exc:`TypeError` and the connection will be closed.
+
+        .. _fragmentation: https://datatracker.ietf.org/doc/html/rfc6455#section-5.4
+
+        :meth:`send` rejects dict-like objects because this is often an error.
+        (If you want to send the keys of a dict-like object as fragments, call
+        its :meth:`~dict.keys` method and pass the result to :meth:`send`.)
+
+        Canceling :meth:`send` is discouraged. Instead, you should close the
+        connection with :meth:`close`. Indeed, there are only two situations
+        where :meth:`send` may yield control to the event loop and then get
+        canceled; in both cases, :meth:`close` has the same effect and is
+        more clear:
+
+        1. The write buffer is full. If you don't want to wait until enough
+           data is sent, your only alternative is to close the connection.
+           :meth:`close` will likely time out then abort the TCP connection.
+        2. ``message`` is an asynchronous iterator that yields control.
+           Stopping in the middle of a fragmented message will cause a
+           protocol error and the connection will be closed.
+
+        When the connection is closed, :meth:`send` raises
+        :exc:`~websockets.exceptions.ConnectionClosed`. Specifically, it
+        raises :exc:`~websockets.exceptions.ConnectionClosedOK` after a normal
+        connection closure and
+        :exc:`~websockets.exceptions.ConnectionClosedError` after a protocol
+        error or a network failure.
+
+        Args:
+            message: Message to send.
+
+        Raises:
+            ConnectionClosed: When the connection is closed.
+            TypeError: If ``message`` doesn't have a supported type.
+
+        """
+        await self.ensure_open()
+
+        # While sending a fragmented message, prevent sending other messages
+        # until all fragments are sent.
+        while self._fragmented_message_waiter is not None:
+            await asyncio.shield(self._fragmented_message_waiter)
+
+        # Unfragmented message -- this case must be handled first because
+        # strings and bytes-like objects are iterable.
+
+        if isinstance(message, (str, bytes, bytearray, memoryview)):
+            opcode, data = prepare_data(message)
+            await self.write_frame(True, opcode, data)
+
+        # Catch a common mistake -- passing a dict to send().
+
+        elif isinstance(message, Mapping):
+            raise TypeError("data is a dict-like object")
+
+        # Fragmented message -- regular iterator.
+
+        elif isinstance(message, Iterable):
+            # Work around https://github.com/python/mypy/issues/6227
+            message = cast(Iterable[Data], message)
+
+            iter_message = iter(message)
+            try:
+                fragment = next(iter_message)
+            except StopIteration:
+                return
+            opcode, data = prepare_data(fragment)
+
+            self._fragmented_message_waiter = self.loop.create_future()
+            try:
+                # First fragment.
+                await self.write_frame(False, opcode, data)
+
+                # Other fragments.
+                for fragment in iter_message:
+                    confirm_opcode, data = prepare_data(fragment)
+                    if confirm_opcode != opcode:
+                        raise TypeError("data contains inconsistent types")
+                    await self.write_frame(False, OP_CONT, data)
+
+                # Final fragment.
+                await self.write_frame(True, OP_CONT, b"")
+
+            except (Exception, asyncio.CancelledError):
+                # We're half-way through a fragmented message and we can't
+                # complete it. This makes the connection unusable.
+                self.fail_connection(CloseCode.INTERNAL_ERROR)
+                raise
+
+            finally:
+                self._fragmented_message_waiter.set_result(None)
+                self._fragmented_message_waiter = None
+
+        # Fragmented message -- asynchronous iterator
+
+        elif isinstance(message, AsyncIterable):
+            # Implement aiter_message = aiter(message) without aiter
+            # Work around https://github.com/python/mypy/issues/5738
+            aiter_message = cast(
+                Callable[[AsyncIterable[Data]], AsyncIterator[Data]],
+                type(message).__aiter__,
+            )(message)
+            try:
+                # Implement fragment = anext(aiter_message) without anext
+                # Work around https://github.com/python/mypy/issues/5738
+                fragment = await cast(
+                    Callable[[AsyncIterator[Data]], Awaitable[Data]],
+                    type(aiter_message).__anext__,
+                )(aiter_message)
+            except StopAsyncIteration:
+                return
+            opcode, data = prepare_data(fragment)
+
+            self._fragmented_message_waiter = self.loop.create_future()
+            try:
+                # First fragment.
+                await self.write_frame(False, opcode, data)
+
+                # Other fragments.
+                async for fragment in aiter_message:
+                    confirm_opcode, data = prepare_data(fragment)
+                    if confirm_opcode != opcode:
+                        raise TypeError("data contains inconsistent types")
+                    await self.write_frame(False, OP_CONT, data)
+
+                # Final fragment.
+                await self.write_frame(True, OP_CONT, b"")
+
+            except (Exception, asyncio.CancelledError):
+                # We're half-way through a fragmented message and we can't
+                # complete it. This makes the connection unusable.
+                self.fail_connection(CloseCode.INTERNAL_ERROR)
+                raise
+
+            finally:
+                self._fragmented_message_waiter.set_result(None)
+                self._fragmented_message_waiter = None
+
+        else:
+            raise TypeError("data must be str, bytes-like, or iterable")
+
+    async def close(
+        self,
+        code: int = CloseCode.NORMAL_CLOSURE,
+        reason: str = "",
+    ) -> None:
+        """
+        Perform the closing handshake.
+
+        :meth:`close` waits for the other end to complete the handshake and
+        for the TCP connection to terminate. As a consequence, there's no need
+        to await :meth:`wait_closed` after :meth:`close`.
+
+        :meth:`close` is idempotent: it doesn't do anything once the
+        connection is closed.
+
+        Wrapping :func:`close` in :func:`~asyncio.create_task` is safe, given
+        that errors during connection termination aren't particularly useful.
+
+        Canceling :meth:`close` is discouraged. If it takes too long, you can
+        set a shorter ``close_timeout``. If you don't want to wait, let the
+        Python process exit, then the OS will take care of closing the TCP
+        connection.
+
+        Args:
+            code: WebSocket close code.
+            reason: WebSocket close reason.
+
+        """
+        try:
+            async with asyncio_timeout(self.close_timeout):
+                await self.write_close_frame(Close(code, reason))
+        except asyncio.TimeoutError:
+            # If the close frame cannot be sent because the send buffers
+            # are full, the closing handshake won't complete anyway.
+            # Fail the connection to shut down faster.
+            self.fail_connection()
+
+        # If no close frame is received within the timeout, asyncio_timeout()
+        # cancels the data transfer task and raises TimeoutError.
+
+        # If close() is called multiple times concurrently and one of these
+        # calls hits the timeout, the data transfer task will be canceled.
+        # Other calls will receive a CancelledError here.
+
+        try:
+            # If close() is canceled during the wait, self.transfer_data_task
+            # is canceled before the timeout elapses.
+            async with asyncio_timeout(self.close_timeout):
+                await self.transfer_data_task
+        except (asyncio.TimeoutError, asyncio.CancelledError):
+            pass
+
+        # Wait for the close connection task to close the TCP connection.
+        await asyncio.shield(self.close_connection_task)
+
+    async def wait_closed(self) -> None:
+        """
+        Wait until the connection is closed.
+
+        This coroutine is identical to the :attr:`closed` attribute, except it
+        can be awaited.
+
+        This can make it easier to detect connection termination, regardless
+        of its cause, in tasks that interact with the WebSocket connection.
+
+        """
+        await asyncio.shield(self.connection_lost_waiter)
+
+    async def ping(self, data: Data | None = None) -> Awaitable[float]:
+        """
+        Send a Ping_.
+
+        .. _Ping: https://datatracker.ietf.org/doc/html/rfc6455#section-5.5.2
+
+        A ping may serve as a keepalive, as a check that the remote endpoint
+        received all messages up to this point, or to measure :attr:`latency`.
+
+        Canceling :meth:`ping` is discouraged. If :meth:`ping` doesn't return
+        immediately, it means the write buffer is full. If you don't want to
+        wait, you should close the connection.
+
+        Canceling the :class:`~asyncio.Future` returned by :meth:`ping` has no
+        effect.
+
+        Args:
+            data: Payload of the ping. A string will be encoded to UTF-8.
+                If ``data`` is :obj:`None`, the payload is four random bytes.
+
+        Returns:
+            A future that will be completed when the corresponding pong is
+            received. You can ignore it if you don't intend to wait. The result
+            of the future is the latency of the connection in seconds.
+
+            ::
+
+                pong_waiter = await ws.ping()
+                # only if you want to wait for the corresponding pong
+                latency = await pong_waiter
+
+        Raises:
+            ConnectionClosed: When the connection is closed.
+            RuntimeError: If another ping was sent with the same data and
+                the corresponding pong wasn't received yet.
+
+        """
+        await self.ensure_open()
+
+        if data is not None:
+            data = prepare_ctrl(data)
+
+        # Protect against duplicates if a payload is explicitly set.
+        if data in self.pings:
+            raise RuntimeError("already waiting for a pong with the same data")
+
+        # Generate a unique random payload otherwise.
+        while data is None or data in self.pings:
+            data = struct.pack("!I", random.getrandbits(32))
+
+        pong_waiter = self.loop.create_future()
+        # Resolution of time.monotonic() may be too low on Windows.
+        ping_timestamp = time.perf_counter()
+        self.pings[data] = (pong_waiter, ping_timestamp)
+
+        await self.write_frame(True, OP_PING, data)
+
+        return asyncio.shield(pong_waiter)
+
+    async def pong(self, data: Data = b"") -> None:
+        """
+        Send a Pong_.
+
+        .. _Pong: https://datatracker.ietf.org/doc/html/rfc6455#section-5.5.3
+
+        An unsolicited pong may serve as a unidirectional heartbeat.
+
+        Canceling :meth:`pong` is discouraged. If :meth:`pong` doesn't return
+        immediately, it means the write buffer is full. If you don't want to
+        wait, you should close the connection.
+
+        Args:
+            data: Payload of the pong. A string will be encoded to UTF-8.
+
+        Raises:
+            ConnectionClosed: When the connection is closed.
+
+        """
+        await self.ensure_open()
+
+        data = prepare_ctrl(data)
+
+        await self.write_frame(True, OP_PONG, data)
+
+    # Private methods - no guarantees.
+
+    def connection_closed_exc(self) -> ConnectionClosed:
+        exc: ConnectionClosed
+        if (
+            self.close_rcvd is not None
+            and self.close_rcvd.code in OK_CLOSE_CODES
+            and self.close_sent is not None
+            and self.close_sent.code in OK_CLOSE_CODES
+        ):
+            exc = ConnectionClosedOK(
+                self.close_rcvd,
+                self.close_sent,
+                self.close_rcvd_then_sent,
+            )
+        else:
+            exc = ConnectionClosedError(
+                self.close_rcvd,
+                self.close_sent,
+                self.close_rcvd_then_sent,
+            )
+        # Chain to the exception that terminated data transfer, if any.
+        exc.__cause__ = self.transfer_data_exc
+        return exc
+
+    async def ensure_open(self) -> None:
+        """
+        Check that the WebSocket connection is open.
+
+        Raise :exc:`~websockets.exceptions.ConnectionClosed` if it isn't.
+
+        """
+        # Handle cases from most common to least common for performance.
+        if self.state is State.OPEN:
+            # If self.transfer_data_task exited without a closing handshake,
+            # self.close_connection_task may be closing the connection, going
+            # straight from OPEN to CLOSED.
+            if self.transfer_data_task.done():
+                await asyncio.shield(self.close_connection_task)
+                raise self.connection_closed_exc()
+            else:
+                return
+
+        if self.state is State.CLOSED:
+            raise self.connection_closed_exc()
+
+        if self.state is State.CLOSING:
+            # If we started the closing handshake, wait for its completion to
+            # get the proper close code and reason. self.close_connection_task
+            # will complete within 4 or 5 * close_timeout after close(). The
+            # CLOSING state also occurs when failing the connection. In that
+            # case self.close_connection_task will complete even faster.
+            await asyncio.shield(self.close_connection_task)
+            raise self.connection_closed_exc()
+
+        # Control may only reach this point in buggy third-party subclasses.
+        assert self.state is State.CONNECTING
+        raise InvalidState("WebSocket connection isn't established yet")
+
+    async def transfer_data(self) -> None:
+        """
+        Read incoming messages and put them in a queue.
+
+        This coroutine runs in a task until the closing handshake is started.
+
+        """
+        try:
+            while True:
+                message = await self.read_message()
+
+                # Exit the loop when receiving a close frame.
+                if message is None:
+                    break
+
+                # Wait until there's room in the queue (if necessary).
+                if self.max_queue is not None:
+                    while len(self.messages) >= self.max_queue:
+                        self._put_message_waiter = self.loop.create_future()
+                        try:
+                            await asyncio.shield(self._put_message_waiter)
+                        finally:
+                            self._put_message_waiter = None
+
+                # Put the message in the queue.
+                self.messages.append(message)
+
+                # Notify recv().
+                if self._pop_message_waiter is not None:
+                    self._pop_message_waiter.set_result(None)
+                    self._pop_message_waiter = None
+
+        except asyncio.CancelledError as exc:
+            self.transfer_data_exc = exc
+            # If fail_connection() cancels this task, avoid logging the error
+            # twice and failing the connection again.
+            raise
+
+        except ProtocolError as exc:
+            self.transfer_data_exc = exc
+            self.fail_connection(CloseCode.PROTOCOL_ERROR)
+
+        except (ConnectionError, TimeoutError, EOFError, ssl.SSLError) as exc:
+            # Reading data with self.reader.readexactly may raise:
+            # - most subclasses of ConnectionError if the TCP connection
+            #   breaks, is reset, or is aborted;
+            # - TimeoutError if the TCP connection times out;
+            # - IncompleteReadError, a subclass of EOFError, if fewer
+            #   bytes are available than requested;
+            # - ssl.SSLError if the other side infringes the TLS protocol.
+            self.transfer_data_exc = exc
+            self.fail_connection(CloseCode.ABNORMAL_CLOSURE)
+
+        except UnicodeDecodeError as exc:
+            self.transfer_data_exc = exc
+            self.fail_connection(CloseCode.INVALID_DATA)
+
+        except PayloadTooBig as exc:
+            self.transfer_data_exc = exc
+            self.fail_connection(CloseCode.MESSAGE_TOO_BIG)
+
+        except Exception as exc:
+            # This shouldn't happen often because exceptions expected under
+            # regular circumstances are handled above. If it does, consider
+            # catching and handling more exceptions.
+            self.logger.error("data transfer failed", exc_info=True)
+
+            self.transfer_data_exc = exc
+            self.fail_connection(CloseCode.INTERNAL_ERROR)
+
+    async def read_message(self) -> Data | None:
+        """
+        Read a single message from the connection.
+
+        Re-assemble data frames if the message is fragmented.
+
+        Return :obj:`None` when the closing handshake is started.
+
+        """
+        frame = await self.read_data_frame(max_size=self.max_size)
+
+        # A close frame was received.
+        if frame is None:
+            return None
+
+        if frame.opcode == OP_TEXT:
+            text = True
+        elif frame.opcode == OP_BINARY:
+            text = False
+        else:  # frame.opcode == OP_CONT
+            raise ProtocolError("unexpected opcode")
+
+        # Shortcut for the common case - no fragmentation
+        if frame.fin:
+            return frame.data.decode() if text else frame.data
+
+        # 5.4. Fragmentation
+        fragments: list[Data] = []
+        max_size = self.max_size
+        if text:
+            decoder_factory = codecs.getincrementaldecoder("utf-8")
+            decoder = decoder_factory(errors="strict")
+            if max_size is None:
+
+                def append(frame: Frame) -> None:
+                    nonlocal fragments
+                    fragments.append(decoder.decode(frame.data, frame.fin))
+
+            else:
+
+                def append(frame: Frame) -> None:
+                    nonlocal fragments, max_size
+                    fragments.append(decoder.decode(frame.data, frame.fin))
+                    assert isinstance(max_size, int)
+                    max_size -= len(frame.data)
+
+        else:
+            if max_size is None:
+
+                def append(frame: Frame) -> None:
+                    nonlocal fragments
+                    fragments.append(frame.data)
+
+            else:
+
+                def append(frame: Frame) -> None:
+                    nonlocal fragments, max_size
+                    fragments.append(frame.data)
+                    assert isinstance(max_size, int)
+                    max_size -= len(frame.data)
+
+        append(frame)
+
+        while not frame.fin:
+            frame = await self.read_data_frame(max_size=max_size)
+            if frame is None:
+                raise ProtocolError("incomplete fragmented message")
+            if frame.opcode != OP_CONT:
+                raise ProtocolError("unexpected opcode")
+            append(frame)
+
+        return ("" if text else b"").join(fragments)
+
+    async def read_data_frame(self, max_size: int | None) -> Frame | None:
+        """
+        Read a single data frame from the connection.
+
+        Process control frames received before the next data frame.
+
+        Return :obj:`None` if a close frame is encountered before any data frame.
+
+        """
+        # 6.2. Receiving Data
+        while True:
+            frame = await self.read_frame(max_size)
+
+            # 5.5. Control Frames
+            if frame.opcode == OP_CLOSE:
+                # 7.1.5.  The WebSocket Connection Close Code
+                # 7.1.6.  The WebSocket Connection Close Reason
+                self.close_rcvd = Close.parse(frame.data)
+                if self.close_sent is not None:
+                    self.close_rcvd_then_sent = False
+                try:
+                    # Echo the original data instead of re-serializing it with
+                    # Close.serialize() because that fails when the close frame
+                    # is empty and Close.parse() synthesizes a 1005 close code.
+                    await self.write_close_frame(self.close_rcvd, frame.data)
+                except ConnectionClosed:
+                    # Connection closed before we could echo the close frame.
+                    pass
+                return None
+
+            elif frame.opcode == OP_PING:
+                # Answer pings, unless connection is CLOSING.
+                if self.state is State.OPEN:
+                    try:
+                        await self.pong(frame.data)
+                    except ConnectionClosed:
+                        # Connection closed while draining write buffer.
+                        pass
+
+            elif frame.opcode == OP_PONG:
+                if frame.data in self.pings:
+                    pong_timestamp = time.perf_counter()
+                    # Sending a pong for only the most recent ping is legal.
+                    # Acknowledge all previous pings too in that case.
+                    ping_id = None
+                    ping_ids = []
+                    for ping_id, (pong_waiter, ping_timestamp) in self.pings.items():
+                        ping_ids.append(ping_id)
+                        if not pong_waiter.done():
+                            pong_waiter.set_result(pong_timestamp - ping_timestamp)
+                        if ping_id == frame.data:
+                            self.latency = pong_timestamp - ping_timestamp
+                            break
+                    else:
+                        raise AssertionError("solicited pong not found in pings")
+                    # Remove acknowledged pings from self.pings.
+                    for ping_id in ping_ids:
+                        del self.pings[ping_id]
+
+            # 5.6. Data Frames
+            else:
+                return frame
+
+    async def read_frame(self, max_size: int | None) -> Frame:
+        """
+        Read a single frame from the connection.
+
+        """
+        frame = await Frame.read(
+            self.reader.readexactly,
+            mask=not self.is_client,
+            max_size=max_size,
+            extensions=self.extensions,
+        )
+        if self.debug:
+            self.logger.debug("< %s", frame)
+        return frame
+
+    def write_frame_sync(self, fin: bool, opcode: int, data: bytes) -> None:
+        frame = Frame(fin, Opcode(opcode), data)
+        if self.debug:
+            self.logger.debug("> %s", frame)
+        frame.write(
+            self.transport.write,
+            mask=self.is_client,
+            extensions=self.extensions,
+        )
+
+    async def drain(self) -> None:
+        try:
+            # drain() cannot be called concurrently by multiple coroutines.
+            # See https://github.com/python/cpython/issues/74116 for details.
+            # This workaround can be removed when dropping Python < 3.10.
+            async with self._drain_lock:
+                # Handle flow control automatically.
+                await self._drain()
+        except ConnectionError:
+            # Terminate the connection if the socket died.
+            self.fail_connection()
+            # Wait until the connection is closed to raise ConnectionClosed
+            # with the correct code and reason.
+            await self.ensure_open()
+
+    async def write_frame(
+        self, fin: bool, opcode: int, data: bytes, *, _state: int = State.OPEN
+    ) -> None:
+        # Defensive assertion for protocol compliance.
+        if self.state is not _state:  # pragma: no cover
+            raise InvalidState(
+                f"Cannot write to a WebSocket in the {self.state.name} state"
+            )
+        self.write_frame_sync(fin, opcode, data)
+        await self.drain()
+
+    async def write_close_frame(self, close: Close, data: bytes | None = None) -> None:
+        """
+        Write a close frame if and only if the connection state is OPEN.
+
+        This dedicated coroutine must be used for writing close frames to
+        ensure that at most one close frame is sent on a given connection.
+
+        """
+        # Test and set the connection state before sending the close frame to
+        # avoid sending two frames in case of concurrent calls.
+        if self.state is State.OPEN:
+            # 7.1.3. The WebSocket Closing Handshake is Started
+            self.state = State.CLOSING
+            if self.debug:
+                self.logger.debug("= connection is CLOSING")
+
+            self.close_sent = close
+            if self.close_rcvd is not None:
+                self.close_rcvd_then_sent = True
+            if data is None:
+                data = close.serialize()
+
+            # 7.1.2. Start the WebSocket Closing Handshake
+            await self.write_frame(True, OP_CLOSE, data, _state=State.CLOSING)
+
+    async def keepalive_ping(self) -> None:
+        """
+        Send a Ping frame and wait for a Pong frame at regular intervals.
+
+        This coroutine exits when the connection terminates and one of the
+        following happens:
+
+        - :meth:`ping` raises :exc:`ConnectionClosed`, or
+        - :meth:`close_connection` cancels :attr:`keepalive_ping_task`.
+
+        """
+        if self.ping_interval is None:
+            return
+
+        try:
+            while True:
+                await asyncio.sleep(self.ping_interval)
+
+                self.logger.debug("% sending keepalive ping")
+                pong_waiter = await self.ping()
+
+                if self.ping_timeout is not None:
+                    try:
+                        async with asyncio_timeout(self.ping_timeout):
+                            # Raises CancelledError if the connection is closed,
+                            # when close_connection() cancels keepalive_ping().
+                            # Raises ConnectionClosed if the connection is lost,
+                            # when connection_lost() calls abort_pings().
+                            await pong_waiter
+                        self.logger.debug("% received keepalive pong")
+                    except asyncio.TimeoutError:
+                        if self.debug:
+                            self.logger.debug("- timed out waiting for keepalive pong")
+                        self.fail_connection(
+                            CloseCode.INTERNAL_ERROR,
+                            "keepalive ping timeout",
+                        )
+                        break
+
+        except ConnectionClosed:
+            pass
+
+        except Exception:
+            self.logger.error("keepalive ping failed", exc_info=True)
+
+    async def close_connection(self) -> None:
+        """
+        7.1.1. Close the WebSocket Connection
+
+        When the opening handshake succeeds, :meth:`connection_open` starts
+        this coroutine in a task. It waits for the data transfer phase to
+        complete then it closes the TCP connection cleanly.
+
+        When the opening handshake fails, :meth:`fail_connection` does the
+        same. There's no data transfer phase in that case.
+
+        """
+        try:
+            # Wait for the data transfer phase to complete.
+            if hasattr(self, "transfer_data_task"):
+                try:
+                    await self.transfer_data_task
+                except asyncio.CancelledError:
+                    pass
+
+            # Cancel the keepalive ping task.
+            if hasattr(self, "keepalive_ping_task"):
+                self.keepalive_ping_task.cancel()
+
+            # A client should wait for a TCP close from the server.
+            if self.is_client and hasattr(self, "transfer_data_task"):
+                if await self.wait_for_connection_lost():
+                    return
+                if self.debug:
+                    self.logger.debug("- timed out waiting for TCP close")
+
+            # Half-close the TCP connection if possible (when there's no TLS).
+            if self.transport.can_write_eof():
+                if self.debug:
+                    self.logger.debug("x half-closing TCP connection")
+                # write_eof() doesn't document which exceptions it raises.
+                # "[Errno 107] Transport endpoint is not connected" happens
+                # but it isn't completely clear under which circumstances.
+                # uvloop can raise RuntimeError here.
+                try:
+                    self.transport.write_eof()
+                except (OSError, RuntimeError):  # pragma: no cover
+                    pass
+
+                if await self.wait_for_connection_lost():
+                    return
+                if self.debug:
+                    self.logger.debug("- timed out waiting for TCP close")
+
+        finally:
+            # The try/finally ensures that the transport never remains open,
+            # even if this coroutine is canceled (for example).
+            await self.close_transport()
+
+    async def close_transport(self) -> None:
+        """
+        Close the TCP connection.
+
+        """
+        # If connection_lost() was called, the TCP connection is closed.
+        # However, if TLS is enabled, the transport still needs closing.
+        # Else asyncio complains: ResourceWarning: unclosed transport.
+        if self.connection_lost_waiter.done() and self.transport.is_closing():
+            return
+
+        # Close the TCP connection. Buffers are flushed asynchronously.
+        if self.debug:
+            self.logger.debug("x closing TCP connection")
+        self.transport.close()
+
+        if await self.wait_for_connection_lost():
+            return
+        if self.debug:
+            self.logger.debug("- timed out waiting for TCP close")
+
+        # Abort the TCP connection. Buffers are discarded.
+        if self.debug:
+            self.logger.debug("x aborting TCP connection")
+        self.transport.abort()
+
+        # connection_lost() is called quickly after aborting.
+        await self.wait_for_connection_lost()
+
+    async def wait_for_connection_lost(self) -> bool:
+        """
+        Wait until the TCP connection is closed or ``self.close_timeout`` elapses.
+
+        Return :obj:`True` if the connection is closed and :obj:`False`
+        otherwise.
+
+        """
+        if not self.connection_lost_waiter.done():
+            try:
+                async with asyncio_timeout(self.close_timeout):
+                    await asyncio.shield(self.connection_lost_waiter)
+            except asyncio.TimeoutError:
+                pass
+        # Re-check self.connection_lost_waiter.done() synchronously because
+        # connection_lost() could run between the moment the timeout occurs
+        # and the moment this coroutine resumes running.
+        return self.connection_lost_waiter.done()
+
+    def fail_connection(
+        self,
+        code: int = CloseCode.ABNORMAL_CLOSURE,
+        reason: str = "",
+    ) -> None:
+        """
+        7.1.7. Fail the WebSocket Connection
+
+        This requires:
+
+        1. Stopping all processing of incoming data, which means cancelling
+           :attr:`transfer_data_task`. The close code will be 1006 unless a
+           close frame was received earlier.
+
+        2. Sending a close frame with an appropriate code if the opening
+           handshake succeeded and the other side is likely to process it.
+
+        3. Closing the connection. :meth:`close_connection` takes care of
+           this once :attr:`transfer_data_task` exits after being canceled.
+
+        (The specification describes these steps in the opposite order.)
+
+        """
+        if self.debug:
+            self.logger.debug("! failing connection with code %d", code)
+
+        # Cancel transfer_data_task if the opening handshake succeeded.
+        # cancel() is idempotent and ignored if the task is done already.
+        if hasattr(self, "transfer_data_task"):
+            self.transfer_data_task.cancel()
+
+        # Send a close frame when the state is OPEN (a close frame was already
+        # sent if it's CLOSING), except when failing the connection because of
+        # an error reading from or writing to the network.
+        # Don't send a close frame if the connection is broken.
+        if code != CloseCode.ABNORMAL_CLOSURE and self.state is State.OPEN:
+            close = Close(code, reason)
+
+            # Write the close frame without draining the write buffer.
+
+            # Keeping fail_connection() synchronous guarantees it can't
+            # get stuck and simplifies the implementation of the callers.
+            # Not drainig the write buffer is acceptable in this context.
+
+            # This duplicates a few lines of code from write_close_frame().
+
+            self.state = State.CLOSING
+            if self.debug:
+                self.logger.debug("= connection is CLOSING")
+
+            # If self.close_rcvd was set, the connection state would be
+            # CLOSING. Therefore self.close_rcvd isn't set and we don't
+            # have to set self.close_rcvd_then_sent.
+            assert self.close_rcvd is None
+            self.close_sent = close
+
+            self.write_frame_sync(True, OP_CLOSE, close.serialize())
+
+        # Start close_connection_task if the opening handshake didn't succeed.
+        if not hasattr(self, "close_connection_task"):
+            self.close_connection_task = self.loop.create_task(self.close_connection())
+
+    def abort_pings(self) -> None:
+        """
+        Raise ConnectionClosed in pending keepalive pings.
+
+        They'll never receive a pong once the connection is closed.
+
+        """
+        assert self.state is State.CLOSED
+        exc = self.connection_closed_exc()
+
+        for pong_waiter, _ping_timestamp in self.pings.values():
+            pong_waiter.set_exception(exc)
+            # If the exception is never retrieved, it will be logged when ping
+            # is garbage-collected. This is confusing for users.
+            # Given that ping is done (with an exception), canceling it does
+            # nothing, but it prevents logging the exception.
+            pong_waiter.cancel()
+
+    # asyncio.Protocol methods
+
+    def connection_made(self, transport: asyncio.BaseTransport) -> None:
+        """
+        Configure write buffer limits.
+
+        The high-water limit is defined by ``self.write_limit``.
+
+        The low-water limit currently defaults to ``self.write_limit // 4`` in
+        :meth:`~asyncio.WriteTransport.set_write_buffer_limits`, which should
+        be all right for reasonable use cases of this library.
+
+        This is the earliest point where we can get hold of the transport,
+        which means it's the best point for configuring it.
+
+        """
+        transport = cast(asyncio.Transport, transport)
+        transport.set_write_buffer_limits(self.write_limit)
+        self.transport = transport
+
+        # Copied from asyncio.StreamReaderProtocol
+        self.reader.set_transport(transport)
+
+    def connection_lost(self, exc: Exception | None) -> None:
+        """
+        7.1.4. The WebSocket Connection is Closed.
+
+        """
+        self.state = State.CLOSED
+        self.logger.debug("= connection is CLOSED")
+
+        self.abort_pings()
+
+        # If self.connection_lost_waiter isn't pending, that's a bug, because:
+        # - it's set only here in connection_lost() which is called only once;
+        # - it must never be canceled.
+        self.connection_lost_waiter.set_result(None)
+
+        if True:  # pragma: no cover
+            # Copied from asyncio.StreamReaderProtocol
+            if self.reader is not None:
+                if exc is None:
+                    self.reader.feed_eof()
+                else:
+                    self.reader.set_exception(exc)
+
+            # Copied from asyncio.FlowControlMixin
+            # Wake up the writer if currently paused.
+            if not self._paused:
+                return
+            waiter = self._drain_waiter
+            if waiter is None:
+                return
+            self._drain_waiter = None
+            if waiter.done():
+                return
+            if exc is None:
+                waiter.set_result(None)
+            else:
+                waiter.set_exception(exc)
+
+    def pause_writing(self) -> None:  # pragma: no cover
+        assert not self._paused
+        self._paused = True
+
+    def resume_writing(self) -> None:  # pragma: no cover
+        assert self._paused
+        self._paused = False
+
+        waiter = self._drain_waiter
+        if waiter is not None:
+            self._drain_waiter = None
+            if not waiter.done():
+                waiter.set_result(None)
+
+    def data_received(self, data: bytes) -> None:
+        self.reader.feed_data(data)
+
+    def eof_received(self) -> None:
+        """
+        Close the transport after receiving EOF.
+
+        The WebSocket protocol has its own closing handshake: endpoints close
+        the TCP or TLS connection after sending and receiving a close frame.
+
+        As a consequence, they never need to write after receiving EOF, so
+        there's no reason to keep the transport open by returning :obj:`True`.
+
+        Besides, that doesn't work on TLS connections.
+
+        """
+        self.reader.feed_eof()
+
+
+# broadcast() is defined in the protocol module even though it's primarily
+# used by servers and documented in the server module because it works with
+# client connections too and because it's easier to test together with the
+# WebSocketCommonProtocol class.
+
+
+def broadcast(
+    websockets: Iterable[WebSocketCommonProtocol],
+    message: Data,
+    raise_exceptions: bool = False,
+) -> None:
+    """
+    Broadcast a message to several WebSocket connections.
+
+    A string (:class:`str`) is sent as a Text_ frame. A bytestring or bytes-like
+    object (:class:`bytes`, :class:`bytearray`, or :class:`memoryview`) is sent
+    as a Binary_ frame.
+
+    .. _Text: https://datatracker.ietf.org/doc/html/rfc6455#section-5.6
+    .. _Binary: https://datatracker.ietf.org/doc/html/rfc6455#section-5.6
+
+    :func:`broadcast` pushes the message synchronously to all connections even
+    if their write buffers are overflowing. There's no backpressure.
+
+    If you broadcast messages faster than a connection can handle them, messages
+    will pile up in its write buffer until the connection times out. Keep
+    ``ping_interval`` and ``ping_timeout`` low to prevent excessive memory usage
+    from slow connections.
+
+    Unlike :meth:`~websockets.legacy.protocol.WebSocketCommonProtocol.send`,
+    :func:`broadcast` doesn't support sending fragmented messages. Indeed,
+    fragmentation is useful for sending large messages without buffering them in
+    memory, while :func:`broadcast` buffers one copy per connection as fast as
+    possible.
+
+    :func:`broadcast` skips connections that aren't open in order to avoid
+    errors on connections where the closing handshake is in progress.
+
+    :func:`broadcast` ignores failures to write the message on some connections.
+    It continues writing to other connections. On Python 3.11 and above, you may
+    set ``raise_exceptions`` to :obj:`True` to record failures and raise all
+    exceptions in a :pep:`654` :exc:`ExceptionGroup`.
+
+    While :func:`broadcast` makes more sense for servers, it works identically
+    with clients, if you have a use case for opening connections to many servers
+    and broadcasting a message to them.
+
+    Args:
+        websockets: WebSocket connections to which the message will be sent.
+        message: Message to send.
+        raise_exceptions: Whether to raise an exception in case of failures.
+
+    Raises:
+        TypeError: If ``message`` doesn't have a supported type.
+
+    """
+    if not isinstance(message, (str, bytes, bytearray, memoryview)):
+        raise TypeError("data must be str or bytes-like")
+
+    if raise_exceptions:
+        if sys.version_info[:2] < (3, 11):  # pragma: no cover
+            raise ValueError("raise_exceptions requires at least Python 3.11")
+        exceptions = []
+
+    opcode, data = prepare_data(message)
+
+    for websocket in websockets:
+        if websocket.state is not State.OPEN:
+            continue
+
+        if websocket._fragmented_message_waiter is not None:
+            if raise_exceptions:
+                exception = RuntimeError("sending a fragmented message")
+                exceptions.append(exception)
+            else:
+                websocket.logger.warning(
+                    "skipped broadcast: sending a fragmented message",
+                )
+            continue
+
+        try:
+            websocket.write_frame_sync(True, opcode, data)
+        except Exception as write_exception:
+            if raise_exceptions:
+                exception = RuntimeError("failed to write message")
+                exception.__cause__ = write_exception
+                exceptions.append(exception)
+            else:
+                websocket.logger.warning(
+                    "skipped broadcast: failed to write message: %s",
+                    traceback.format_exception_only(
+                        # Remove first argument when dropping Python 3.9.
+                        type(write_exception),
+                        write_exception,
+                    )[0].strip(),
+                )
+
+    if raise_exceptions and exceptions:
+        raise ExceptionGroup("skipped broadcast", exceptions)
+
+
+# Pretend that broadcast is actually defined in the server module.
+broadcast.__module__ = "websockets.legacy.server"