ExamAdept

In Python, what is the purpose of using a double underscore prefix before a variable, such as __price?

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

A:

To indicate a public variable

B:

To define a private variable

C:

To create a class method

D:

To allow unrestricted access to the variable

Answer: B

The double underscore prefix (__price) indicates that it is a private variable, demonstrating encapsulation by hiding the implementation details.

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How can encapsulation help improve code maintenance?

A:

By exposing all internal details of an object

B:

By hiding the implementation details of an object

C:

By making all variables public for easy access

D:

By using global variables extensively

Answer: B

Encapsulation helps improve code maintenance by hiding the implementation details of an object, making it easier to modify or extend without affecting other parts of the code.

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In Python, how can encapsulation be enhanced to provide write access to a private variable 'value'?

class Example:
    def __init__(self):
        self._value = 0

A:

Create a setter method for 'value'

B:

Use a double underscore prefix for 'value'

C:

Use a single underscore prefix for 'value'

D:

Make 'value' a global variable

Answer: A

To provide write access to a private variable, a setter method can be created to set the value.

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Consider the following Python class:

class Student:
    def __init__(self, name, age):
        self._name = name
        self._age = age

    def display_student_info(self):
        return f"Name: {self._name}, Age: {self._age}"

What encapsulation concept is demonstrated in this code?

A:

Public access specifier

B:

Private access specifier

C:

Protected access specifier

D:

Global variable

Answer: B

The single underscore prefix (_) in the variables _name and _age indicates that they are private variables, demonstrating encapsulation by hiding the implementation details.

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What is the primary purpose of encapsulating the 'balance' variable in the following Python class?

class BankAccount:
    def __init__(self, balance):
        self._balance = balance

    def get_balance(self):
        return self._balance

A:

To create a new instance of the class

B:

To make the 'balance' variable public

C:

To provide controlled access to the 'balance' variable

D:

To allow unrestricted access to the 'balance' variable

Answer: C

Encapsulation is used to provide controlled access to variables, and in this case, it is applied to the 'balance' variable.

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Questions for: Encapsulation