code: func WithLogger(logger *log.Logger) memberSetOption {
  	return func(g *memberSet) error {
  		g.stdLogger = logger
  		return nil
  	}
  }
docs: // WithLogger is a functional option for providing a Go logger to NewMemberSet.
  // If the memberSet's transport is nil, this logger will be used when creating
  // one. If WithLogOutput is not used, this logger will be passed to memberlist
  // for it to use internally. This logger is not used for logging by code in this
  // (gossip) package - for that, use the WithPilosaLogger option.