Top 50 Most Frequently Asked Python Interview Questions & Answers (Beginner to Advanced Guide)
Python is one of the most in-demand programming languages in today’s job market. Whether you are a fresher or an experienced developer, Python interview questions often test both fundamentals and real-world problem-solving skills.
This blog covers 50 most frequently asked Python interview questions, categorized into Beginner, Intermediate, and Advanced levels, with clear answers packed with technical keywords to help you crack interviews confidently.
Why Python Interviews Focus on Concepts
Python interviews are designed to test:
- Core programming fundamentals
- Object-Oriented Programming (OOP)
- Memory management and performance
- Real-world usage and scalability
- Future-ready skills like automation, data handling, and backend development
Let’s dive into the top 50 Python interview questions with answers.
🟢 Beginner-Level Python Interview Questions (1–20)
1. What is Python?
Python is a high-level, interpreted, dynamically typed programming language known for readability, simplicity, and a vast standard library.
2. What are Python’s key features?
- Interpreted language
- Dynamic typing
- Object-oriented and functional support
- Automatic memory management (Garbage Collection)
3. What is PEP 8?
PEP 8 is Python’s official style guide that defines coding conventions for readability and maintainability.
4. Difference between list and tuple
- List: Mutable, slower, uses more memory
- Tuple: Immutable, faster, memory-efficient
5. What is dynamic typing in Python?
Variable types are determined at runtime, not during compilation.
6. What are Python keywords?
Reserved words like def, class, return, yield, used to define syntax.
7. What is indentation in Python?
Indentation defines code blocks instead of braces {}—it is syntactically mandatory.
8. What is a function in Python?
A reusable block of code defined using the def keyword.
9. What are Python modules?
Files containing Python code that can be imported using import.
10. What is a package?
A directory containing multiple modules and an __init__.py file.
11. What are comments in Python?
Used for documentation and ignored by the interpreter (# for single-line).
12. What is a variable?
A reference to a memory location storing data.
13. Difference between = and ==
=assigns value==compares values
14. What is typecasting?
Converting one data type to another using int(), float(), str().
15. What is a dictionary?
An unordered collection of key-value pairs using hashing.
16. What is slicing?
Extracting a portion of sequences using [start:end:step].
17. What is None in Python?
Represents the absence of a value.
18. What is the input() function?
Takes user input as a string.
19. What is len()?
Returns the length of a sequence.
20. What is Python interpreter?
Executes Python code line by line.
🟡 Intermediate-Level Python Interview Questions (21–35)
21. What is OOP in Python?
Object-Oriented Programming using classes, objects, inheritance, polymorphism, encapsulation.
22. What is a class?
A blueprint for creating objects.
23. What is __init__ method?
A constructor used to initialize object attributes.
24. What is inheritance?
A mechanism to derive a class from another class.
25. What is polymorphism?
Same method name behaving differently for different objects.
26. What is encapsulation?
Restricting access to data using private variables.
27. What are decorators?
Functions that modify other functions using @decorator.
28. What are generators?
Functions that yield values using yield, enabling lazy evaluation.
29. Difference between is and ==
is: identity comparison==: value comparison
30. What is exception handling?
Handling runtime errors using try-except-finally.
31. What is multithreading?
Running multiple threads concurrently for I/O-bound tasks.
32. What is GIL (Global Interpreter Lock)?
A mutex that allows only one thread to execute Python bytecode at a time.
33. What is a lambda function?
Anonymous function defined using lambda.
34. What is file handling?
Reading/writing files using open(), read(), write().
35. What is virtual environment?
An isolated Python environment using venv or virtualenv.
🔴 Advanced-Level Python Interview Questions (36–50)
36. What is memory management in Python?
Managed using reference counting and garbage collection.
37. What is garbage collection?
Automatic removal of unused objects to free memory.
38. What is multiprocessing?
Running processes in parallel to bypass GIL for CPU-bound tasks.
39. Difference between shallow copy and deep copy
- Shallow: Copies references
- Deep: Copies entire object hierarchy
40. What are metaclasses?
Classes that define the behavior of other classes.
41. What is monkey patching?
Dynamically modifying a class or module at runtime.
42. What is asyncio?
Library for writing asynchronous, non-blocking code.
43. What is REST API in Python?
Using frameworks like Flask or FastAPI to build APIs.
44. What is serialization?
Converting objects to byte streams using pickle or json.
45. What are Python descriptors?
Objects that manage attribute access.
46. What is Duck Typing?
Object suitability determined by behavior, not type.
47. What is CPython?
Default Python implementation written in C.
48. What is PyPy?
Alternative Python interpreter with JIT compilation.
49. What is dependency injection?
Providing dependencies externally for loose coupling.
50. How is Python future-ready?
Python powers AI, ML, DevOps, Cloud, Automation, Data Science, making it future-proof.
Pro Tips
- Focus on concepts + examples
- Practice coding daily
- Understand why, not just what
- Learn Python internals (GIL, memory model)
- Combine Python with SQL, APIs, and Git
Common Mistakes to Avoid
- Memorizing answers without understanding
- Ignoring Python internals
- Not practicing real-world problems
- Weak grasp on OOP concepts
- Skipping error handling and optimization