quiz 6

Question 1

Every Python class requires:

Answer 1

a constructor method

Question 2

Is it impossible to create a static variable in a Python class.

Answer 2

False

Question 2

What is the output of the following code?

class Lion():
def __init__(self, x=”Scar”):
self.x = x

def roar(self):
        print(self.x)

new_lion = Lion()

print(new_lion.roar())

Answer 2

“Scar”

Question 3

How many instance variables will exist after you run the following code?

class Person():
def __init__(self, weight = 160):
self.weight = weight

next_person = Person(150)
next_person.foot_size = 10
next_person.eyes = “green”

Answer 3

4

Question 4

What is the output of the following:

class Tiger():
def __init__(self, x):
self.x = x
self.change(self.x)

def change(self, y):
    y = "Evil"

new_tiger = Tiger(“Kind”)

print(new_tiger.x)

Answer 4

“Kind”

Question 5

What does inheritance mean in object-oriented programming?

Answer 5

Ability of a class to derive members of parent class as a part of its definition

Question 6

In Python you can derive a class from two parent classes but not from three parent classes.

Answer 6

False

Question 7

What is the output of the following code?

class Big_Cat:
def __init__(self):
self.x = “dangerous”

class Cat(Big_Cat):
def __init__(self):
self.y = “quiet”

new_cat = Cat()

print(new_cat.x, new_cat.y)

Answer 7

This generates an error.

Question 8

To define an object x in Python that inherits its attributes and methods from a parent class y, we use x = subclass(y).

Answer 8

False

Question 9

How would one define the function of the “-“ (minus) operator for a new class?

Answer 9

define a __sub__() method on the class.