Mastering Python Concepts

What is the purpose of a function in Python?

• To define classes and objects.

• To execute code in a sequential manner.

• To encapsulate code for reuse and organization.

• To create variables for data storage.

Answer explanation

The purpose of a function in Python is to encapsulate code for reuse and organization. This allows developers to write modular code, making it easier to maintain and understand, unlike the other options which do not capture this essence.

How do you define a function in Python?

• def function_name(parameters):

• create function_name(parameters)

• function function_name(parameters)

• function_name(parameters) =>

Answer explanation

In Python, functions are defined using the 'def' keyword followed by the function name and parameters in parentheses. The correct syntax is 'def function_name(parameters):', which clearly indicates the start of a function definition.

What keyword is used to return a value from a function?

• yield

• send

• return

• output

Answer explanation

The keyword 'return' is used in functions to send a value back to the caller. Unlike 'yield', which is used in generators, 'return' immediately exits the function and provides the specified value.

What is the output of the following code: print(5 > 3 and 2 < 4)?

• True

• False

• 5 < 3

• 2 > 4

Answer explanation

The expression '5 > 3' evaluates to True and '2 < 4' also evaluates to True. The 'and' operator returns True only if both conditions are True, so the output of the code is True.

How do you write an if-else statement in Python?

• if condition: do_something else: do_something_else

• if condition: do_something; else: do_something_else

• if (condition) { do_something } else { do_something_else }

• if condition do_something else do_something_else

Answer explanation

The correct if-else statement in Python uses indentation to define blocks. The format 'if condition: do_something else: do_something_else' is the proper syntax, while the other options either use incorrect syntax or are from different programming languages.

What will be the output of the following code: if x := 10: print('x is 10')?

• x is not defined

• x is 5

• x equals 10

• x is 10

Answer explanation

The code uses the walrus operator ':=' to assign 10 to x. Since the condition is true, it executes the print statement, resulting in 'x is 10'. Thus, the correct answer is 'x is 10'.

What is the difference between '==' and 'is' in Python?

• '==' is used for comparing strings, while 'is' is used for comparing numbers.

• The '==' operator checks for value equality, while 'is' checks for object identity.

• '==' checks for object identity, while 'is' checks for value equality.

• Both '==' and 'is' check for value equality.

Answer explanation

The correct choice explains that '==' checks for value equality, meaning it compares the values of two objects, while 'is' checks for object identity, determining if two references point to the same object in memory.

What is a class in Object-Oriented Programming?

• A class is a collection of data without any methods.

• A class is a type of variable in programming.

• A class is a blueprint for creating objects that defines attributes and methods.

• A class is a function that executes code.

Answer explanation

A class in Object-Oriented Programming serves as a blueprint for creating objects, defining their attributes (data) and methods (functions). This distinguishes it from other options that misrepresent the concept.

How do you create an object from a class in Python?

• You create an object by importing the class: from MyClass import my_object

• You instantiate a class using the new keyword: my_object = new MyClass()

• You create an object by defining a variable: my_object := MyClass

• You create an object by calling the class: my_object = MyClass()

Answer explanation

You create an object in Python by calling the class with parentheses, like this: my_object = MyClass(). This instantiates the class and creates an object, which is the correct method to create an object.

What is inheritance in OOP?

• Inheritance allows classes to be combined into a single class.

• Inheritance is a way to create multiple instances of a class.

• Inheritance is a mechanism in object-oriented programming that enables a new class to inherit attributes and behaviors from an existing class.

• Inheritance is a method for storing data in a database.

Answer explanation

The correct choice defines inheritance as a mechanism in OOP that allows a new class to inherit attributes and behaviors from an existing class, promoting code reuse and establishing a relationship between classes.