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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:
 def read_message( self, callback: Callable[["Future[Union[None, str, bytes]]"], None] = None ) -> Awaitable[Union[None, str, bytes]]: """Reads a message from the WebSocket server. If on_message_callback was specified at WebSocket initialization, this function will never return messages Returns a future whose result is the message, or None if the connection is closed. If a callback argument is given it will be called with the future when it is ready. """


        awaitable = self.read_queue.get()
        if callback is not None:
            self.io_loop.add_future(asyncio.ensure_future(awaitable), callback)
        return awaitable