code: func (api *Client) GetChannelReplies(channelID, thread_ts string) ([]Message, error) {
  	return api.GetChannelRepliesContext(context.Background(), channelID, thread_ts)
  }
docs: // GetChannelReplies gets an entire thread (a message plus all the messages in reply to it).
  // see https://api.slack.com/methods/channels.replies