code: func GetFactory(out io.Writer) func(context.Context) logging.Logger {
  	lock := sync.Mutex{}
  	return func(c context.Context) logging.Logger {
  		return &jsonLogger{
  			ctx:  c,
  			lock: &lock,
  			out:  out,
  		}
  	}
  }
docs: // GetFactory creates a goroutine safe gkelogger that writes into out.