code: func MsgOptionAttachments(attachments ...Attachment) MsgOption {
  	return func(config *sendConfig) error {
  		if attachments == nil {
  			return nil
  		}
  
  		attachments, err := json.Marshal(attachments)
  		if err == nil {
  			config.values.Set("attachments", string(attachments))
  		}
  		return err
  	}
  }
docs: // MsgOptionAttachments provide attachments for the message.