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: warm-backend-minio.go
    path of file: ./repos/minio/cmd
    
    the code of the file until where you have to start completion: // Copyright (c) 2015-2022 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your
    
func newWarmBackendMinIO(conf madmin.TierMinIO, tier string) (*warmBackendMinIO, error) {
	// Validation of credentials
	if conf.AccessKey == "" || conf.SecretKey == "" {
		return nil, errors.New("both access and secret keys are required")
	}

	if conf.Bucket == "" {
		return nil, errors.New("no bucket name was provided")
	}

	u, err := url.Parse(conf.Endpoint)
	if err != nil {
		return nil, err
	}

	creds := credentials.NewStaticV4(conf.AccessKey, conf.SecretKey, "")

	getRemoteTierTargetInstanceTransportOnce.Do(func() {
		getRemoteTierTargetInstanceTransport = NewHTTPTransportWithTimeout(10 * time.Minute)
	})
	opts := &minio.Options{
		Creds:     creds,
		Secure:    u.Scheme == "https",
		Transport: getRemoteTierTargetInstanceTransport,
	}
	client, err := minio.New(u.Host, opts)
	if err != nil {
		return nil, err
	}
	client.SetAppInfo(fmt.Sprintf("minio-tier-%s", tier), ReleaseTag)

	core := &minio.Core{Client: client}
	return &warmBackendMinIO{
		warmBackendS3{
			client: client,
			core:   core,
			Bucket: conf.Bucket,
			Prefix: strings.TrimSuffix(conf.Prefix, slashSeparator),
		},
	}, nil
}