Merge duplicate CNCONTACT array swift 3 contacts framework

I did find duplicate contacts list from this method , now i'm stuck in merging the duplicates, any idea how i can do this.

I fetched duplicate using this code Referenced from previous question.

let formatter = CNContactFormatter()
formatter.style = .fullName

let keys = [CNContactIdentifierKey as CNKeyDescriptor, CNContactFormatter.descriptorForRequiredKeys(for: .fullName)]
let request = CNContactFetchRequest(keysToFetch: keys)
var contactsByName = [String: [CNContact]]()
try! self.store.enumerateContacts(with: request) { contact, stop in
    guard let name = formatter.string(from: contact) else { return }
    contactsByName[name] = (contactsByName[name] ?? []) + [contact]   // or in Swift 4, `contactsByName[name, default: []].append(contact)`
}
let duplicates = contactsByName.filter { $1.count > 1 }

If you followed my previous answer for fetching duplicates list after you can use this code to merge duplicates.

func mergeAllDuplicates() -> CNContact {

    let duplicates: [Array<CNContact>] = //Array of Duplicates Contacts

    for item in duplicates {

        // CNCONTACT PROPERTIES

        var namePrefix: [String] = [String]()
        var givenName: [String] = [String]()
        var middleName: [String] = [String]()
        var familyName: [String] = [String]()
        var previousFamilyName: [String] = [String]()
        var nameSuffix: [String] = [String]()
        var nickname: [String] = [String]()
        var organizationName: [String] = [String]()
        var departmentName: [String] = [String]()
        var jobTitle: [String] = [String]()
        var phoneNumbers: [CNPhoneNumber] = [CNPhoneNumber]()
        var emailAddresses: [NSString] = [NSString]()
        var postalAddresses: [CNPostalAddress] = [CNPostalAddress]()
        var urlAddresses: [NSString] = [NSString]()

        var contactRelations: [CNContactRelation] = [CNContactRelation]()
        var socialProfiles: [CNSocialProfile] = [CNSocialProfile]()
        var instantMessageAddresses: [CNInstantMessageAddress] = [CNInstantMessageAddress]()

        // Filter
        for items in item {
            namePrefix.append(items.namePrefix)
            givenName.append(items.givenName)
            middleName.append(items.middleName)
            familyName.append(items.familyName)
            previousFamilyName.append(items.previousFamilyName)
            nameSuffix.append(items.nameSuffix)
            nickname.append(items.nickname)
            organizationName.append(items.organizationName)
            departmentName.append(items.departmentName)
            jobTitle.append(items.jobTitle)

            for number in items.phoneNumbers {
                phoneNumbers.append(number.value)
            }
            for email in items.emailAddresses {
                emailAddresses.append(email.value)
            }
            for postal in items.postalAddresses {
                postalAddresses.append(postal.value)
            }
            for url in items.urlAddresses {
                urlAddresses.append(url.value)
            }
            for relation in items.contactRelations {
                contactRelations.append(relation.value)
            }
            for social in items.socialProfiles {
                socialProfiles.append(social.value)
            }
            for message in items.instantMessageAddresses {
                instantMessageAddresses.append(message.value)
            }

        }

        let newContact = CNMutableContact()
        newContact.namePrefix = Array(Set(namePrefix))[0]
        newContact.givenName = Array(Set(givenName))[0]
        newContact.middleName = Array(Set(middleName))[0]
        newContact.familyName = Array(Set(familyName))[0]
        newContact.previousFamilyName = Array(Set(previousFamilyName))[0]
        newContact.nameSuffix = Array(Set(nameSuffix))[0]
        newContact.nickname = Array(Set(nickname))[0]
        newContact.organizationName = Array(Set(namePrefix))[0]
        newContact.departmentName = Array(Set(namePrefix))[0]
        newContact.jobTitle = Array(Set(namePrefix))[0]
        for item in Array(Set(phoneNumbers)) {
            newContact.phoneNumbers.append(CNLabeledValue(label: CNLabelHome, value: item))
        }
        for item in Array(Set(emailAddresses)) {
            newContact.emailAddresses.append(CNLabeledValue(label: CNLabelHome, value: item))
        }
        for item in Array(Set(postalAddresses)) {
            newContact.postalAddresses.append(CNLabeledValue(label: CNLabelHome, value: item))
        }
        for item in Array(Set(urlAddresses)) {
            newContact.urlAddresses.append(CNLabeledValue(label: CNLabelHome, value: item))
        }
        for item in Array(Set(contactRelations)) {
            newContact.contactRelations.append(CNLabeledValue(label: CNLabelHome, value: item))
        }
        for item in Array(Set(socialProfiles)) {
            newContact.socialProfiles.append(CNLabeledValue(label: CNLabelHome, value: item))
        }
        for item in Array(Set(instantMessageAddresses)) {
            newContact.instantMessageAddresses.append(CNLabeledValue(label: CNLabelHome, value: item))
        }

        return newContact

    }
}

This approach will take quite a memory so I suggest, use this approach as a reference.