Hackerrank Object-Oriented Programming Basics 2

Question 1

Which method is automatically called when an object is created from a class?

Accepted Answer

__init__

Answer

__new__

Answer

__create__

Answer

__start__

Question 2

What does the 'self' parameter in an instance method refer to?

Accepted Answer

The current instance of the class

Answer

The class itself

Answer

The parent class

Answer

A global variable

Question 3

What will the following code output?
class Dog:
    def __init__(self, name):
        self.name = name
d = Dog('Rex')
print(d.name)

Accepted Answer

Rex

Answer

Dog

Answer

self.name

Answer

None

Question 4

Which keyword is used to inherit from a parent class in Python?

Accepted Answer

The parent class is passed in parentheses

Answer

extends

Answer

implements

Answer

inherits

Question 5

What is a class attribute vs an instance attribute?

Accepted Answer

Class attributes are shared by all instances; instance attributes are unique per object

Answer

Class attributes are defined inside __init__; instance attributes are defined outside

Answer

Class attributes are private; instance attributes are public

Answer

There is no difference between them

Question 6

Which built-in function returns the class (type) of an object?

Accepted Answer

type()

Answer

isinstance()

Answer

classof()

Answer

getclass()

Question 7

What does 'encapsulation' mean in OOP?

Accepted Answer

Data and methods are bundled together, with controlled access

Answer

A class can inherit from multiple parent classes

Answer

A method can take any number of arguments

Answer

Objects of a child class can replace parent class objects