Mix of conceptual questions in interviews for Python developer

1. Language Fundamentals & Syntax

Example Question: What are Python’s key features?
How to Answer: Mention readability, dynamic typing, interpreted nature, extensive libraries, portability, and support for multiple paradigms.

2. Data Structures and Algorithms

Example Question: How do you find the first non-repeating character in a string?
How to Answer: Explain using a hash map (dictionary) to count frequencies, then iterate again for the first unique character. Discuss time and space complexity.

3. OOP Concepts in Python

Example Question: What is the difference between a class method and a static method?
How to Answer: Class methods receive the class as the first argument, static methods do not receive any implicit arguments. Provide examples using @classmethod and @staticmethod decorators.

4. Error Handling & Debugging

Example Question: How do you handle exceptions in Python?
How to Answer: Discuss try-except blocks, optionally with else and finally clauses. Emphasize writing specific exception handlers to avoid catching all exceptions blindly.

5. Libraries & Frameworks

Example Question: How do you work with virtual environments and package management?
How to Answer: Explain creating isolated environments using venv or pipenv, installing packages with pip, and importance of requirements.txt for dependencies.

6. Coding Problems

Example Question: Implement a function to merge two sorted lists.
How to Answer: Write Python code using two pointers to create a sorted merged list, and explain the approach and complexity.

7. System Design / Architecture

Example Question: Design a URL shortening service using Python.
How to Answer: Outline components like database for mapping URLs, hashing function or unique ID generation, API design, scalability concerns, and caching.

8. Testing & Quality Assurance

Example Question: How do you test your Python code?
How to Answer: Talk about unittest or pytest frameworks, test-driven development, mocking dependencies, and continuous integration.

9. Concurrency & Performance

Example Question: What is the Global Interpreter Lock (GIL)? How do you work around it?
How to Answer: Explain GIL restricts execution of bytecode to one thread, affecting CPU-bound threading. Mention multiprocessing or async programming as workarounds.

10. Behavioral Questions

Example Question: Tell me about a challenging bug you fixed.
How to Answer: Use STAR method—Situation, Task, Action, Result. Explain the problem, debugging steps, and eventual resolution.