import LocalAuthentication

    func showTouchID() {
        let context = LAContext()
        context.localizedCancelTitle = "Cancel"
        context.localizedFallbackTitle = "Unlock with password"

        var error: NSError?
        if context.canEvaluatePolicy(.deviceOwnerAuthenticationWithBiometrics, error: &error) {
            let reason = "unlock AllYourPasswords"

            context.evaluatePolicy(.deviceOwnerAuthenticationWithBiometrics, localizedReason: reason ) { success, error in

                if success {
                    // Move to the main thread because a state update triggers UI changes.
                    DispatchQueue.main.async { [unowned self] in
                        self.showPasswords()
                    }

                } else {
                    print(error?.localizedDescription ?? "Failed to authenticate")
                }
            }
        }
    }