code: func MsgOptionPostEphemeral(userID string) MsgOption {
  	return func(config *sendConfig) error {
  		config.endpoint = config.apiurl + string(chatPostEphemeral)
  		MsgOptionUser(userID)(config)
  		config.values.Del("ts")
  
  		return nil
  	}
  }
docs: // MsgOptionPostEphemeral - posts an ephemeral message to the provided user.