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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_rtm_message(self, channel_id, text):
 """Send a Slack message to a channel over RTM. :param channel_id: a slack channel id. :param text: a slack message. Serverside formatting is done in a similar way to normal user message; see `Slack's docs <https://api.slack.com/docs/formatting>`__. """


        message = {
            'id': self._current_message_id,
            'type': 'message',
            'channel': channel_id,
            'text': text,
        }
        self.ws.send(json.dumps(message))
        self._current_message_id += 1