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Python Programming - Encapsulation

Exercise : Encapsulation - General Questions
  • Encapsulation - General Questions
96.
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
Use a getter method for 'product_code'
Add a single underscore prefix before 'product_code'
Make 'product_code' a global variable
Add a double underscore prefix before 'product_code'
Answer: Option
Explanation:
Adding a double underscore prefix before 'product_code' makes it a private variable, enforcing encapsulation within the class.
97.
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?
To retrieve the area of the triangle
To set a new area for the triangle
To calculate the area of the triangle
To expose all internal details of the class
Answer: Option
Explanation:
The calculate_area() method calculates and returns the area of the triangle, demonstrating encapsulation.
98.
In Python, what is the benefit of using a private variable with a double underscore prefix, such as __stock_quantity? 
class Inventory:
    __stock_quantity = 0

    def update_stock(self, quantity):
        Inventory.__stock_quantity += quantity
It improves code maintainability by hiding implementation details
It allows unrestricted access to __stock_quantity
It exposes all internal details of __stock_quantity
It creates a global variable
Answer: Option
Explanation:
Encapsulation with a double underscore prefix improves code maintainability by hiding the implementation details of the class attribute __stock_quantity.
99.
What is the primary purpose of the following Python class? 
class Person:
    def __init__(self, name, __age):
        self.name = name
        self.__age = __age

    def get_age(self):
        return self.__age
To create a new instance of the class
To provide controlled access to the 'age' variable
To define a public variable 'age'
To allow unrestricted access to the 'age' variable
Answer: Option
Explanation:
The get_age() method provides controlled and read-only access to the private variable '__age', demonstrating encapsulation.
100.
How can encapsulation be enforced in Python to make a variable 'reservation_code' accessible only within its own class? 
class Reservation:
    def __init__(self, reservation_code, __status):
        self.reservation_code = reservation_code
        self.__status = __status
Use a getter method for 'reservation_code'
Add a single underscore prefix before 'reservation_code'
Make 'reservation_code' a global variable
Add a double underscore prefix before 'reservation_code'
Answer: Option
Explanation:
Adding a double underscore prefix before 'reservation_code' makes it a private variable, enforcing encapsulation within the class.
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