Python Method Overriding and Dynamic Dispatch

Quick Answer

The correct answer is method overriding, because the SavingsAccount subclass redefines the withdraw method from BankAccount to add penalty logic while preserving the same method signature. This is the defining characteristic of method overriding in Python: a subclass provides its own specific implementation of a method already defined in its superclass, allowing dynamic dispatch at runtime to call the appropriate version based on the object’s actual type. On the Certified Associate Python Programmer PCAP exam, this concept tests your understanding of inheritance and polymorphism, often appearing in questions that ask you to identify the design pattern when a subclass alters a parent method’s behavior. A common trap is confusing overriding with overloading—remember that Python does not support true method overloading; overriding always involves the same method name and parameters. Memory tip: think “override = replace the parent’s version” and “overload = same name, different arguments (not Python’s style).”