I’m preparing for upcoming interviews and want to brush up on frequently asked Python topics. From your experience, what are some of the most popular Python interview questions that test both fundamentals and practical skills?
For example, questions about differences between lists and tuples, the use of if __name__ == "__main__":, working with lambda functions, decorators, file handling, or data structures.
It would be great if you could share a concise list or examples of Python questions that often appear in interviews, especially for developer or data engineering roles.
I’ve gone through several Python interviews over the past few years, and here are some topics that almost always come up. If you focus on these, you’ll be in a solid position:
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Data Structures - Be ready to explain lists, tuples, sets, and dictionaries. Interviewers often ask about mutability, time complexity, and when to use each.
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Functions and Decorators - Expect questions on *args, **kwargs, and decorators (how they modify function behavior).
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OOP Concepts - Classes, inheritance, and special methods like init or str.
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Exception Handling - Write or explain simple try-except blocks.
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File Handling - Use of with open() for safe resource management.
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Modules and Packages - Understanding imports and the role of init.py.
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if name == “main”: - Know why it’s used to control script execution.
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Lambda and List Comprehension - Simple, one-liner expressions are favorites.
From experience, I’d also say problem-solving with small coding challenges (like reversing strings, sorting lists, or counting words) shows your comfort level best.
You can also check out these Python interview questions and answers.
From my own interview prep, I found it helpful to group questions into three buckets - core syntax, problem-solving, and applied Python:
Core Syntax: Data types, loops, conditionals, functions
Problem-Solving: String manipulation, searching/sorting, using built-in libraries like collections
Applied Python: File I/O, decorators, and using generators for performance
One tip - always explain your reasoning instead of just stating the answer. Interviewers love when you say why something works the way it does.
Having interviewed and been interviewed for Python roles, I’ve noticed a consistent pattern. Most interviewers focus on how well you understand Pythonic principles - not just syntax.
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Know how to write clean, readable code using comprehensions.
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Understand mutable vs immutable types and their implications.
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Be comfortable with error handling and debugging using tools like pdb.
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Learn some data structure basics from collections (e.g., Counter, defaultdict).
If you can walk through your logic confidently and show familiarity with real-world coding practices, that stands out more than memorizing theory.