Implement Polymorphic Processing for Different Subclass Types

You are building a small payment-fee calculation module. Implement a base PaymentMethod class that provides a general fee-calculation mechanism and several subclasses that override or extend that behavior: - CreditCard: percentage fee of 2.0%. - PayPal: percentage fee of 2.9% plus a fixed 30-cent surcharge. - BankTransfer: no fee. - LoyaltyCard: behaves like a CreditCard but provides a 50-cent discount on the calculated fee (fee can't go below zero). All fee calculations are in integer cents. The base class should encapsulate the percent-based calculation so subclasses can reuse it (use super() where appropriate). Finally, implement compute_total_fee(transactions) which accepts a list of (payment_method_instance, amount_in_cents) and returns the total fee (int) across all transactions. This exercise focuses on correct use of inheritance, overriding, super(), and writing polymorphic code that calls the same method on different subclass instances.

Use inheritance and polymorphism to implement different fee-calculation behaviors in subclasses, use super() to reuse base logic, and write a function that processes a list of transactions polymorphically.

All amounts and fees are non-negative integers. Use integer arithmetic for fee calculations. Do not print; return the integer value.