Python Object-Oriented Programming Basics 4

Question 1

What is a mixin in Python OOP?

Accepted Answer

A small class designed to add specific behavior via multiple inheritance

Answer

Mixins are narrowly focused classes added to a class hierarchy via multiple inheritance to inject reusable behavior without deep coupling.

Question 2

What does `__slots__` do when defined in a class?

Accepted Answer

Replaces `__dict__` to restrict instance attributes to a fixed set

Answer

Declaring `__slots__` removes the per-instance `__dict__`, reducing memory and preventing dynamic attribute creation.

Question 3

Which of the following is an example of polymorphism in Python?

Accepted Answer

Two classes both define a `speak()` method with different behaviors

Answer

Polymorphism allows different classes to implement the same interface (e.g., `speak()`), enabling generic code to work with multiple types.

Question 4

What is the difference between `@classmethod` and `@staticmethod`?

Accepted Answer

Class methods receive `cls`; static methods receive neither `self` nor `cls`

Answer

`@classmethod` passes the class as its first argument (`cls`), while `@staticmethod` is a plain function scoped to the class.

Question 5

In Python, what does `__del__` define?

Accepted Answer

A destructor called when the object is about to be garbage collected

Answer

`__del__` is the finalizer, invoked just before the interpreter destroys the object, though its exact timing is not guaranteed.

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