Python interview questions along with their answers

 

Object-Oriented Programming (OOP) Questions:

1. What is encapsulation in Python?

   • Encapsulation is the bundling of data and methods that operate on the data into a single unit, known as a class. It hides the internal state of an object from the outside world and only exposes a controlled interface.

2. What is inheritance in Python?

   • Inheritance is the mechanism by which a class can inherit properties and behavior from another class. The class being inherited from is called the base or parent class, and the class that inherits is called the derived or child class.

3. Explain method overriding in Python.

   • Method overriding occurs when a subclass provides a specific implementation of a method that is already defined in its superclass. The overridden method in the subclass takes precedence over the method with the same name in the superclass.

4. What is polymorphism in Python?

   • Polymorphism refers to the ability of different objects to respond to the same message or method invocation in different ways. It allows objects of different classes to be treated as objects of a common superclass.

Exception Handling Questions:

5. What is exception handling in Python?

   • Exception handling is a mechanism to handle errors or exceptional situations that occur during program execution. It allows you to gracefully recover from errors and prevent the program from crashing.

6. Explain the try-except block in Python.

   • The try-except block is used for exception handling in Python. Code that might raise an exception is placed inside the try block, and the corresponding exception handling code is placed inside the except block.

7. What is the purpose of the finally block in Python exception handling?

• The finally block is used to execute code that should always run, regardless of whether an exception occurs or not. It is typically used for cleanup tasks such as closing files or releasing resources.

File Handling Questions:

8. How do you open and read a file in Python?

   • You can open a file using the open() function and then read its contents using methods like read(), readline(), or readlines().

9. Explain the difference between reading a file in text mode vs binary mode.

   • When reading a file in text mode, Python interprets the contents of the file as a sequence of characters encoded using a specific character encoding (e.g., UTF-8). In binary mode, the file is read as a sequence of bytes, with no character encoding applied.

Data Structures and Algorithms Questions:

10. What is the difference between a list and a tuple in Python?

    • Lists are mutable, meaning their elements can be modified after creation, whereas tuples are immutable, meaning their elements cannot be changed once the tuple is created.

11. Explain the concept of Big O notation.

    • Big O notation is used to describe the performance or complexity of an algorithm in terms of its worst-case scenario. It provides a way to compare the efficiency of different algorithms by focusing on the growth rate of the algorithm's runtime as the input size increases.

12. What is a set in Python?

    • A set is an unordered collection of unique elements. It is useful for tasks that involve testing for membership, removing duplicates from a sequence, and computing mathematical operations like intersection, union, and difference.

Python Libraries and Frameworks Questions:

13. What is the purpose of the NumPy library in Python?

    • NumPy is a library for numerical computing in Python. It provides support for large, multi-dimensional arrays and matrices, along with a collection of mathematical functions to operate on these arrays efficiently.

14. What is Flask in Python?

• Flask is a lightweight web framework for Python. It is designed to make it easy to build web applications quickly and with minimal code. Flask is known for its simplicity and flexibility, making it a popular choice for building small to medium-sized web applications.