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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 async def recv(self) -> Data: """ This coroutine receives the next message. It returns a :class:`str` for a text frame and :class:`bytes` for a binary frame. When the end of the message stream is reached, :meth:`recv` raises :exc:`~websockets.exceptions.ConnectionClosed`. This can happen after a normal connection closure, a protocol error or a network failure. .. versionchanged:: 3.0 :meth:`recv` used to return ``None`` instead. Refer to the changelog for details. 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.wait_for`. .. versionchanged:: 7.0 Calling :meth:`recv` concurrently raises :exc:`RuntimeError`. """

        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],
                    loop=self.loop,
                    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:
                    assert self.state in [State.CLOSING, State.CLOSED]
                    # 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