如何在Cloudkit中创建新的共享记录，而不是父记录的所有者？

import CloudKit

// 获取默认的CloudKit容器
let container = CKContainer.default()

// 进行身份验证
container.accountStatus { (accountStatus, error) in
    if accountStatus == .available {
        // 创建父记录的唯一标识符
        let parentRecordID = CKRecord.ID(recordName: "parentRecordID")

        // 创建CKReference对象，将其设置为共享记录的父记录
        let parentReference = CKRecord.Reference(recordID: parentRecordID, action: .none)

        // 创建新的CKRecord对象
        let record = CKRecord(recordType: "RecordType")
        record["propertyName"] = "propertyValue"

        // 创建CKShare对象
        let share = CKShare(rootRecord: record)
        share[CKShare.SystemFieldKey.title] = "Share Title" as CKRecordValue
        share[CKShare.SystemFieldKey.shareType] = "com.example.shareType" as CKRecordValue
        share[CKShare.SystemFieldKey.publicPermission] = CKShare.Permission.readWrite as CKRecordValue
        share[CKShare.SystemFieldKey.participants] = [CKShare.ParticipantLookupInfo]()

        // 设置CKShare对象的权限和角色
        let participant = CKShare.ParticipantLookupInfo(userIdentity: CKUserIdentityLookupInfo(userRecordID: nil), emailAddress: nil)
        participant.permission = .readOnly
        participant.role = .participant
        share[CKShare.SystemFieldKey.participants] = [participant]

        // 生成分享URL
        let shareURL = container.shareURL(for: share)

        // 将CKRecord对象和CKShare对象一起保存到CloudKit中
        let operation = CKModifyRecordsOperation(recordsToSave: [record, share], recordIDsToDelete: nil)
        operation.savePolicy = .changedKeys
        operation.modifyRecordsCompletionBlock = { (savedRecords, deletedRecordIDs, error) in
            if error == nil {
                // 共享记录创建成功
                print("Shared record created successfully.")
            } else {
                // 共享记录创建失败
                print("Failed to create shared record. Error: \(error!.localizedDescription)")
            }
        }

        // 执行操作
        container.privateCloudDatabase.add(operation)
    } else {
        // 用户未登录iCloud账号或者没有权限访问CloudKit
        print("User is not logged in to iCloud or does not have permission to access CloudKit.")
    }
}