func _delegateToAppleDelegateMapping() -> [Selector: Selector] {
        
        typealias pkDidSelectShippingMethodSignature = (
            (PKPaymentAuthorizationControllerDelegate) -> (
                PKPaymentAuthorizationController, PKShippingMethod,
                @escaping (PKPaymentRequestShippingMethodUpdate) -> Void
            ) -> Void
        )?
        let pk_didSelectShippingMethod = #selector(
            (PKPaymentAuthorizationControllerDelegate.paymentAuthorizationController(
                _:didSelectShippingMethod:handler:)) as? pkDidSelectShippingMethodSignature)
        let stp_didSelectShippingMethod = #selector(
            _stpinternal_STPApplePayContextDelegateBase.applePayContext(_:didSelect:handler:))
        let pk_didSelectShippingContact = #selector(
            PKPaymentAuthorizationControllerDelegate.paymentAuthorizationController(
                _:didSelectShippingContact:handler:))
        let stp_didSelectShippingContact = #selector(
            _stpinternal_STPApplePayContextDelegateBase.applePayContext(_:didSelectShippingContact:handler:))

        return [
            pk_didSelectShippingMethod: stp_didSelectShippingMethod,
            pk_didSelectShippingContact: stp_didSelectShippingContact,
        ]
    }

Need to resolve this error

(PKPaymentAuthorizationControllerDelegate.paymentAuthorizationController(
                _:didSelectShippingMethod:handler:)) as? pkDidSelectShippingMethodSignature)

Argument of ‘#selector’ does not refer to an ‘@objc’ method, property, or initializer