How to Prepare for a Python Developer Interview
Python job boards are always busy. It is one of the most popular programming languages with seasoned developers, as well as newcomers in the field.
Python is now the second-most popular programming language in the world, coming in just behind JavaScript, according to RedMonk. There are an enormous number of fields you could program for. Do spend time considering where your interests lie.
For example, Python is used in algorithmic trading and popular platforms like Interactive Brokers enable connections to live markets using Python. Top research organizations like NASA and CERN use it. Industrial Light and Magic uses Python to support their special effects work. Python is used extensively at Google and they are looking to hire more developers with this skill.
First Steps
When you find a Python developer vacancy, you need to bag an interview. This is typically done through an e-mail application, cover letter, followed by a call-back.
Since Python vacancies can have hundreds of applicants, this is an important process for the employer who seeks to narrow down their list of candidates to find what they’re looking for.
Once you have a foot through the door and have an interview lined up, you have your next challenge: to showcase your abilities and see whether the placement ticks the boxes for your needs.
What’s In It for the Employer?
Much like the phone interview (if you have one), the interviewer has a set of abilities they want candidates to showcase with confidence and competence.
By asking questions about your professional experience and testing your knowledge, they can get an idea of whether you’re the right person for the role.
What’s in It for Me?
Most importantly, you’ll find out if you’re suited for the job and whether you can take on the challenge. It’s also a good opportunity to practice coding on the spot since developer interviews normally have test exercises.
You also have the opportunity to interact with one or more people from the company you’re applying to, and to get an impression of how the team operates. Finding a team you can perform in is just as important as fitting the technical and professional specifications of a job.
The Gauntlet: Who You Interview With
Typically, Python developer interviews are held by managing members of:
- Internal and external recruitment teams
- HR teams
- Senior development teams.
- Relevant project managers are also involved in the interview process, although this may happen at a later point.
The interview can be hosted in various formats, which will also determine who’s conducting it. You can have one-to-one interviews, group interviews, workshop interviews, phone interviews, and Zoom interviews. Perhaps you’ll have all of them, or only one.
Irrespective of the interview format, the interviewer seeks to find out whether you’re suited for the job. They’re not there to torture you, so a positive approach is to enter the room with a confident, collaborative mindset.
The Basics of Interviewing
Before we address Python-specifics, it’s important to reiterate the purpose of an interview. Not only do you want to showcase your technical coding skills, but your skills to work with other people and collaborate.
There can be other candidates who have the same or better technical knowledge than you. If you make a good impression at the interview, you’ve just maximized your chances of getting further.
Companies tend to look for:
- Presentability: Appearance at work is becoming more and more informal, although employers still seek well-groomed candidates. There’s no need to dress for a black-tie event. On the other hand, you don’t even want to find yourself dressing as Will Smith from Pursuit of Happyness on fuboTV . Find something that’s socially considered as “normal” and you’ll most likely be fine.
- Initiative: Employers like it when interviewees are aware of the company they’re applying to. This doesn’t mean rote-learning 100 facts, but an hour or two of informal reading about the company’s niche and general position in the market. They may not ask, but if they do, you’ll have something to say.
- Attention: If you can’t listen and respond in a job interview, your interviewer will probably and accurately assume that you’d do the same at work.
Technical Interview Preparation for Python Developers
The main technical subjects interviewers ask about are:
- Knowledge of Python required by the level of the role.
- Example projects to get an idea of your previous work and its quality.
- Ability to spot and solve problems.
- General Interview Questions About Programming
You’ll be asked a set of general technical questions related to computer science and programming.
These questions are centered on data structures and algorithms and are just as important to ace as the Python-specific questions. Your answer gives an impression of your ability to develop code with multiple languages and successfully integrate them into a working product.
Some questions you might come across are:
- What are your greatest strengths and weaknesses as a developer?
- What programming languages are you fluent with?
- What development tools do you use and why?
- How does a linked list work?
- How do you find all possible permutations of a string?
There are many more possibilities for general computer science questions, but these should give you an idea of the breadth.
Artificial Intelligence
Many Python jobs relate to AI and machine learning so be prepared for some questions like these:
- What is “deep learning”?
- When would you choose R or Python for a machine learning application?
- What are eigenvalues and eigenvectors?
- What is the difference between supervised and unsupervised learning?
Python Specific Interview Questions
Some specific Python developer interview questions you may encounter during an interview session are:
- What is a namespace?
- List 10 Python functions and one possible use case for each one.
- How does Python manage exceptions?
- What are docstrings?
- What are the major changes between Python 2.x and 3.x?.
- What is encapsulation?
- What is an ‘object()’ in Python and what is its functionality?
- How do you implement multithreading in Python?
There are many other Python-specific questions floating around the internet.
Python Exercises
During your interview, you will likely be asked to complete at least one practical exercise.
These exercises could be at any time during the interview — or even assigned as “homework.” It really depends on the employer and their particular screening process to find the right candidate for the job.
Familiarize yourself with standard coding examples. There are an enormous number of them online. You can start with SimplePrograms and branch out from there.
After the Python Developer Interview
After the interview, be sure you reach out to your contact and thank them for the interview. This will help you to stand out in a crowded field.
Additionally, some HR people expect candidates to do this and assume those who don’t aren’t really interested in the job.
After that, it’s about waiting for a call-back. Most companies who conduct their interviews professionally will get back to you with feedback about how you performed, although this shouldn’t be expected from every employer.
Many employers have hundreds of applications, meaning they won’t take the time to respond to everyone.
By following the advice we’ve listed and preparing well, you should be in a good position to succeed.