ExamAdept

Consider the following Python code:

class Triangle:
    def __init__(self, __base, __height):
        self.__base = __base
        self.__height = __height

    def calculate_area(self):
        return 0.5 * self.__base * self.__height

What is the purpose of the calculate_area() method?

A:

To retrieve the area of the triangle

B:

To set a new area for the triangle

C:

To calculate the area of the triangle

D:

To expose all internal details of the class

Answer: C

The calculate_area() method calculates and returns the area of the triangle, demonstrating encapsulation.

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How can encapsulation be enforced in Python to make a variable 'product_code' accessible only within its own class?

class Product:
    def __init__(self, product_code, __price):
        self.product_code = product_code
        self.__price = __price

A:

Use a getter method for 'product_code'

B:

Add a single underscore prefix before 'product_code'

C:

Make 'product_code' a global variable

D:

Add a double underscore prefix before 'product_code'

Answer: D

Adding a double underscore prefix before 'product_code' makes it a private variable, enforcing encapsulation within the class.

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What is the primary purpose of the following Python class?

class Car:
    def __init__(self, model, __speed):
        self.model = model
        self.__speed = __speed

    def get_speed(self):
        return self.__speed

A:

To create a new instance of the class

B:

To provide controlled access to the 'speed' variable

C:

To define a public variable 'speed'

D:

To allow unrestricted access to the 'speed' variable

Answer: B

The get_speed() method provides controlled and read-only access to the private variable '__speed', demonstrating encapsulation.

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In Python, what is the benefit of using a private variable with a double underscore prefix, such as __inventory_count?

class Product:
    __inventory_count = 0

    def update_inventory(self, count):
        Product.__inventory_count += count

A:

It improves code maintainability by hiding implementation details

B:

It allows unrestricted access to __inventory_count

C:

It exposes all internal details of __inventory_count

D:

It creates a global variable

Answer: A

Encapsulation with a double underscore prefix improves code maintainability by hiding the implementation details of the class attribute __inventory_count.

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Consider the following Python code:

class Rectangle:
    def __init__(self, __length, __width):
        self.__length = __length
        self.__width = __width

    def calculate_area(self):
        return self.__length * self.__width

What is the purpose of the calculate_area() method?

A:

To retrieve the area of the rectangle

B:

To set a new area for the rectangle

C:

To calculate the area of the rectangle

D:

To expose all internal details of the class

Answer: C

The calculate_area() method calculates and returns the area of the rectangle, demonstrating encapsulation.

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Questions for: Encapsulation