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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 send(self, msg, timeout=None, callback=None, raw=False):
        '''
        Send given message, and return a future
        '''
        message_id = self._message_id()
        header = {'mid': message_id}

        future = tornado.concurrent.Future()
        if callback is not None:
            def handle_future(future):
                response = future.result()
                self.io_loop.add_callback(callback, response)
            future.add_done_callback(handle_future)
        # Add this future to the mapping
        self.send_future_map[message_id] = future

        if self.opts.get('detect_mode') is True:
            timeout = 1

        if timeout is not None:
            send_timeout = self.io_loop.call_later(timeout, self.timeout_message, message_id)
            self.send_timeout_map[message_id] = send_timeout

        # if we don't have a send queue, we need to spawn the callback to do the sending
        if not self.send_queue:
            self.io_loop.spawn_callback(self._stream_send)
        self.send_queue.append((message_id, salt.transport.frame.frame_msg(msg, header=header)))
        return future