DCS2103- Week 12 (Objects and Classes)

Word Cloud

What is one thing you remember from Object Oriented Programming?

Multiple Choice

What is a class in Python?

• A class in Python is a type of variable that stores data only.
• A class in Python is a function that performs calculations.
• A class in Python is a method for handling exceptions.
• A class in Python is a blueprint for creating objects that encapsulate data and functionality.

Multiple Choice

Which keyword is used to create a class?

• define
• function
• create
• class

Multiple Choice

What does self refer to?

• A method to initialize class variables.
• The instance of the class in object-oriented programming.
• A keyword for defining global variables.
• A reference to the parent class in inheritance.

Multiple Choice

What is the output?
class A:

x = 5

a1 = A()

a2 = A()

print(a1.x, a2.x)

• 5 4
• 4 5
• 5 5
• 5 6

Multiple Choice

What will happen if a class has no init?

• The class will automatically inherit from a parent class.
• The class will raise an error due to missing parameters.
• The class will use a default constructor, and instance variables may not be initialized.
• The class will have all instance variables set to zero.

Multiple Choice

What is the purpose of str?

• To parse strings into data types.
• To convert objects to their string representation.
• To format strings for display purposes.
• To concatenate multiple strings together.

Multiple Choice

What happens if you modify a class variable using the class?

• Modifying a class variable using the class affects all instances of that class.
• Modifying a class variable only affects the current instance.
• Changing a class variable has no impact on other instances.
• Class variables cannot be modified directly from the class.

Multiple Choice

Calling an instance method from the class without passing an object causes:

• ValueError

• TypeError

• NameError

• No error

Multiple Choice

Which method lets you modify class attributes?

• Class methods (@classmethod)

• Static methods (@staticmethod)

• Instance methods
• Abstract methods

Open Ended

Explain the difference between instance variables and class variables using a real-life example.

Feature	Instance Variable	Class Variable
Belongs to	Each object individually	The class itself
Shared among objects	No	Yes
Example	Student's name, grade	School name, total students
Changes affect	Only that object	All objects