code: def info(self, channel_id):
          
          resource = 'v1/channel.info?channel_id={}'.format(channel_id)
          resp = self._rtm_client.get(resource)
          if resp.is_fail():
              raise RTMServiceError("Failed to get channel information", resp)
  
          return resp.data['result']
docs: Gets channel information by channel id
  
          Args:
              channel_id(int): the id of channel
  
          Returns:
              Channel
  
          Throws:
              RTMServiceError when request failed