Why Python is Popular in Technical Interviews

Python is widely used in:

• Web development
• Data Science & Machine Learning
• Automation & Scripting
• Backend development
• AI & Cloud applications

Its simplicity and readability make it a favorite language for interview coding rounds.

🟢 Basic Python Interview Questions

1. What is Python?

Python is a high-level, interpreted, object-oriented programming language known for readability and simplicity.

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2. What are Python’s key features?

• Easy syntax
• Dynamically typed
• Interpreted
• Object-oriented
• Large standard library
• Cross-platform

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3. What is the difference between list and tuple?

List	Tuple
Mutable	Immutable
Uses []	Uses ()
Slower	Faster

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4. What is a Python dictionary?

A dictionary is a mutable collection of key-value pairs.

student = {"name": "John", "age": 21}

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5. What are Python data types?

• int
• float
• str
• list
• tuple
• dict
• set
• bool

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6. What is dynamic typing?

Python determines variable type at runtime.

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7. What is PEP 8?

PEP 8 is Python’s style guide for writing clean and readable code.

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8. What is indentation in Python?

Indentation defines code blocks instead of curly braces.

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9. What is a lambda function?

square = lambda x: x * x

Anonymous single-line function.

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10. What is the difference between deep copy and shallow copy?

• Shallow copy copies references
• Deep copy copies actual objects

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🔵 OOP in Python Interview Questions

11. What is OOP?

Object-Oriented Programming is based on objects and classes.

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12. What is a class?

class Car:
    def __init__(self, brand):
        self.brand = brand

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13. What is inheritance?

One class inherits properties of another class.

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14. What is polymorphism?

Same method name behaves differently.

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15. What is encapsulation?

Binding data and methods together inside a class.

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16. What is abstraction?

Hiding internal implementation details.

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17. What is method overloading in Python?

Python doesn’t support traditional overloading, but default arguments can simulate it.

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18. What is method overriding?

Child class modifies parent class method.

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19. What is init?

Constructor method called when object is created.

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20. What is self in Python?

Represents the instance of the class.

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🟣 Advanced Python Interview Questions

21. What are decorators?

Functions that modify other functions.

def decorator(func):
    def wrapper():
        print("Before function call")
        func()
    return wrapper

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22. What are generators?

Functions using yield to return iterator.

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23. What is GIL (Global Interpreter Lock)?

It allows only one thread to execute Python bytecode at a time.

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24. What is multithreading?

Running multiple threads concurrently.

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25. What is multiprocessing?

Running multiple processes in parallel.

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26. What are list comprehensions?

squares = [x*x for x in range(5)]

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27. What is monkey patching?

Modifying code at runtime.

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28. What is a virtual environment?

Isolated Python environment for dependencies.

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29. What is pip?

Python package installer.

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30. What is exception handling?

try:
    x = 1/0
except ZeroDivisionError:
    print("Error")

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🔴 Coding & Logic-Based Questions

31. Reverse a string in Python

s = "hello"
print(s[::-1])

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32. Check if a number is prime

def is_prime(n):
    if n < 2:
        return False
    for i in range(2, int(n**0.5)+1):
        if n % i == 0:
            return False
    return True

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33. Find factorial using recursion

def factorial(n):
    if n == 0:
        return 1
    return n * factorial(n-1)

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34. Find duplicates in a list

nums = [1,2,2,3]
duplicates = set([x for x in nums if nums.count(x) > 1])

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35. Merge two dictionaries

dict3 = {**dict1, **dict2}

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36. Find largest element in a list

Use max() function.

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37. Check palindrome

def is_palindrome(s):
    return s == s[::-1]

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38. Count word frequency

from collections import Counter
Counter("hello world".split())

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39. Remove duplicates from list

list(set(nums))

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40. Sort dictionary by value

sorted_dict = dict(sorted(d.items(), key=lambda x: x[1]))

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🟡 Scenario-Based & Tricky Questions

41. Difference between is and ==?

• == compares values
• is compares memory location

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42. What are mutable and immutable types?

Mutable: list, dict, set
Immutable: int, str, tuple

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43. What is str vs repr?

• __str__ → user-friendly
• __repr__ → developer-friendly

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44. What is Python’s garbage collection?

Automatic memory management system.

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45. What are *args and **kwargs?

Used to pass variable number of arguments.

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46. What is slicing?

Extracting parts of sequences using [start:end:step].

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47. What is unpacking?

Assigning elements of iterable to variables.

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48. Difference between append() and extend()?

• append() adds single element
• extend() adds multiple elements

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49. What is name == “main“?

Ensures code runs only when script executed directly.

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50. What is Python used for in 2026?

• AI & Machine Learning
• Backend APIs
• Automation
• Cloud computing
• Data analytics

Final Thoughts

Mastering these Top 50 Python Interview Questions (2026 Updated) will significantly boost your confidence in technical interviews.

If you’re preparing seriously, combine theory + coding practice + mock interviews for best results.