You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: command_remote_configure.go
    path of file: ./repos/seaweedfs/weed/shell
    
    the code of the file until where you have to start completion: package shell

import (
	"context"
	"flag"
	"fmt"
	"github.com/seaweedfs/seaweedfs/weed/filer"
	"github.com/seaweedfs/seaweedfs/weed/pb/filer_pb"
	"github.com/seaweedfs/seaweedfs/weed/pb/remote_pb"
	"github.com/seaweedfs/seaweedfs/weed/remote_storage"
	"github.com/seaweedfs/seaweedf
    
func (c *commandRemoteConfigure) listExistingRemoteStorages(commandEnv *CommandEnv, writer io.Writer) error {

	return filer_pb.ReadDirAllEntries(commandEnv, util.FullPath(filer.DirectoryEtcRemote), "", func(entry *filer_pb.Entry, isLast bool) error {
		if len(entry.Content) == 0 {
			fmt.Fprintf(writer, "skipping %s\n", entry.Name)
			return nil
		}
		if !strings.HasSuffix(entry.Name, filer.REMOTE_STORAGE_CONF_SUFFIX) {
			return nil
		}
		conf := &remote_pb.RemoteConf{}

		if err := proto.Unmarshal(entry.Content, conf); err != nil {
			return fmt.Errorf("unmarshal %s/%s: %v", filer.DirectoryEtcRemote, entry.Name, err)
		}

		// change secret key to stars
		conf.S3SecretKey = strings.Repeat("*", len(conf.S3SecretKey))
		conf.AliyunSecretKey = strings.Repeat("*", len(conf.AliyunSecretKey))
		conf.BaiduAccessKey = strings.Repeat("*", len(conf.BaiduAccessKey))
		conf.FilebaseSecretKey = strings.Repeat("*", len(conf.FilebaseSecretKey))
		conf.StorjSecretKey = strings.Repeat("*", len(conf.StorjSecretKey))
		conf.TencentSecretKey = strings.Repeat("*", len(conf.TencentSecretKey))
		conf.WasabiSecretKey = strings.Repeat("*", len(conf.WasabiSecretKey))

		return filer.ProtoToText(writer, conf)

	})

}