if userDefined[xhttp.AmzStorageClass] == storageclass.STANDARD {
		delete(userDefined, xhttp.AmzStorageClass)
	}

	if opts.WantChecksum != nil && opts.WantChecksum.Type.IsSet() {
		userDefined[hash.MinIOMultipartChecksum] = opts.WantChecksum.Type.String()
	}

	modTime := opts.MTime
	if opts.MTime.IsZero() {
		modTime = UTCNow()
	}