When scaling your team, finding the right Python developer can be a challenge. A poor hiring decision can lead to setbacks, low-quality code, and wasted time. Here, we look at Python interview questions you can use to find the perfect technical and cultural fit for your team.
Questions to ask when interviewing a Python developer
Before diving into the technical details, it can be helpful to start with a few questions to assess a candidate’s approach to technical problems, their knowledge of the latest ecosystem developments, and how they might collaborate with your team. Here are a few questions you can use in your next interview:
- Can you describe a challenging Python project you’ve worked on and the solutions you implemented to overcome the challenges?
- How do you stay up to date with the latest Python developments and best practices?
- Describe a situation where you had to optimise Python code for performance. What techniques did you use, and what was the outcome?
- How do you approach debugging in Python when you encounter an issue in your code?
- Can you give an example of a time when you had to collaborate with team members on a Python project? How did you ensure effective communication and teamwork?
- What is your preferred Python development environment, and can you explain why you like it?
- Have you worked with any Python web frameworks (e.g., Django, or Flask)? If so, can you discuss your experience and projects related to them?
- Can you provide an example of a challenging Python problem you encountered and how you approached solving it?
Python technical interview questions
Now that you’ve covered a few behavioural questions, you can move on to assessing a candidate’s technical ability. Here, we’ll look at some general interview questions, plus a few specific questions for Python developers at different levels of seniority.
Some general technical questions for Python developers include:
- What is PEP 8, and why is it important?
- Can you explain the Global Interpreter Lock (GIL) in Python and its implications for multi-threading?
- What is the difference between Python 2 and Python 3, and what version should you use for new projects?
- Explain the differences between lists, tuples, and sets in Python.
- How does Python’s garbage collection work, and why is it important?
- Describe decorators in Python and provide an example of their use.
- Explain the concept of Python virtual environments and why they are useful.
- How do you handle exceptions and errors in Python, and what is the purpose of the try, except, and finally blocks?
- Can you explain the difference between “deep copy” and “shallow copy” in Python?
- What are list comprehensions, and why are they preferred over traditional for-loops in Python?
If you’re interviewing for junior or intermediate Python developers, consider including a few of these questions:
- Explain the differences between Python 2 and Python 3. Why should new projects use Python 3?
- How do you comment on a single-line and a multi-line block of code in Python?
- Describe the purpose of Python’s zip() function and provide an example of its usage.
- What is the difference between append() and extend() methods for lists in Python?
- Explain the concepts of pass by value and pass by reference in Python. How are function arguments passed?
- Discuss the concept of variable scope in Python. What is the difference between local and global variables?
- How do you open and close files in Python, and why is it important to close them?
For more senior Python developers, more advanced questions might be appropriate:
- What are decorators in Python? Provide an example of a custom decorator function.
- Explain the Global Interpreter Lock (GIL) in Python and its implications for multi-threading.
- How can you use generators and iterators in Python to efficiently work with large data sets?
- Describe the use of context managers in Python and provide an example.
- How can you implement a singleton pattern in Python?
- How to Run a Technical Interview to Hire Developers Efficiently
- How We Conduct a Screening Interview with Developers at OfferZen
- Conducting a technical assessment
- How OfferZen Uses the Panel Interview to Hire Great Developers
- Hire Python developers from South Africa and beyond
- Everything you need to know about hiring Python developers on OfferZen
- Python developer job description