Python Interview Questions

Post a Job

Are you a job seeker? Find jobs

How long have you spent coding primarily in Python? See answer
What would you say are the top three benefits of Python? See answer
How do you track versions of your code? See answer
How do you identify bugs in your code? See answer
Do you ever multithread? See answer
What would you say are the most common mistakes made using Python? See answer
Do you use Python in any of your personal projects? See answer
Describe the differences between shallow and deep copy when using Python. See answer
What do you like most about using Python?
What do you enjoy least about using Python?
Describe to me the key features of Python.
Can you explain the benefits of Flask?
Explain to me how code checking works when using Python.
Do you have experience writing comments using Python?
Demonstrate the difference between a tuple and list.
Have you ever made a deep copy in Python?
Tell me about a time when you used pickling and unpickling in Python.
Describe how slicing works in Python.

Show more questions Show fewer questions

8 Python Interview Questions and Answers

Q:

How long have you spent coding primarily in Python?

A:

You likely won’t encounter (or need) a coder who has worked exclusively with the Python language. What’s more important is how long they’ve been working in Python. This question gives the candidate a chance to talk about their experience in general and explain their preference for Python.

What to look for in an answer:

Evidence they have been working with Python for a significant period of time
Confirmation they are comfortable with the language
An excitement about working with Python

Example:

“I used to code with Java, but I’ve been using Python for the last seven years. It’s just more efficient, and I think it’s appealing that it can operate on different systems. I can get more code written, and it’s so much easier to read.”

Q:

What would you say are the top three benefits of Python?

A:

Knowing why your candidate has chosen to master Python helps you uncover their level of knowledge and more. Importantly, it clues you into their coding style and you can make sure what they prioritize about the language is aligned with the role they’ll fill at your company.

What to look for in an answer:

Advanced knowledge about the coding language
Thoughtfulness about how to best use Python
Evidence they use Python in a way that would benefit your development team

Example:

“I’ve always thought Python was easier to learn, so it’s more accessible to most beginning coders. That was actually the thing that convinced me to learn it in the first place. Secondly, it has much better readability than C++ or Java. I also like that when I run into a problem, there is usually more than one tried and true way to resolve it.”

Q:

How do you track versions of your code?

A:

This question helps you probe the candidate’s organization skills. You’ll want your developer to have more than just coding chops; they should also be able to properly organize and store the data.

What to look for in an answer:

General organization skills
Understanding of the importance of tracking changes to code
Evidence they have created a system for saving different versions

Example:

“I swear by version control. Without it, it’s impossible to figure out who made which changes to the base code or find out when bugs got into the program. With each version saved under its own file name, it’s easier to correct a mistake and figure out a way to stop it from happening again.”

Q:

How do you identify bugs in your code?

A:

Troubleshooting is a vital skill in almost any role, but certainly in a coding role. Asking a specific question about common problems determines that your candidate knows how to address the issue and that their solution will work at your company.

What to look for in an answer:

Indication they know how to problem solve in Python
Evidence they address bugs as they appear in the code
Understanding of available tools for handling bugs

Example:

“I use PyChecker to find bugs in the source code. I prefer it to other programs because it also points out the complexity of the bug.”

Q:

Do you ever multithread?

A:

When written as intended, Python is designed to run a single thread at a time and the Global Interpreter Lock (GIL) ensures it. If your organization has a policy about how you use or don’t use multithreading workarounds, this question will help you assess if the candidate has the same philosophy or is at least amenable to yours.

What to look for in an answer:

Evidence they understand Python’s relationship to multithreading
Confirmation they have thought about the pros and cons
Indication they can work within your company’s policy

Example:

“I usually think multithreading creates more problems than it solves. Sure, it lets the system access more than one thread at a time, but at the cost of memory and CPU. It also makes the code more difficult to debug. I’ve also experienced deadlocks when I multithread, so I tend to avoid it.”

Q:

What would you say are the most common mistakes made using Python?

A:

Getting a look at both your candidate’s mastery of Python and big picture understanding of its pitfalls is important. This question gets to the heart of both issues.

What to look for in an answer:

Evidence they have a thorough understanding about common mistakes in Python
Confirmation they know how to handle mistakes when they happen
Indications their ability to avoid mistakes has grown over time

Example:

“Of course, beginners make the old mistake of using tabs instead of spaces, but there are other common mistakes. One of the things other programmers forget to do is run a code analysis on a regular basis to catch stuff like typos and undefined variables. Generic identifiers are another problem I see a lot, but luckily those are easy to fix.”

Q:

Do you use Python in any of your personal projects?

A:

It may seem like a candidate’s personal projects are none of your business, but the way a candidate answers this question can reveal a lot about their professional interests. When a candidate spends their free time experimenting or honing their skill set with Python, your company can reap the benefits.

What to look for in an answer:

Passion for using Python
Evidence of innovation and desire to create
Awareness about lots of ways to use the coding language

Example:

“Yes, I have created tons of websites using Python, and I’m currently working on an app. In fact, this will be my third Android app and I think it’s the best one I’ve worked on. Working on my own projects is usually where I push the boundaries.”

Q:

Describe the differences between shallow and deep copy when using Python.

A:

When determining a candidate's knowledge of and experience using Python, it's important to ask basic to advanced questions about the various features used to operate the program. Strong candidates should have a general idea of how different coding and programming features work. They should also have impressive communication abilities to effectively break down these features and use simple terminology to explain how they work to potential clients or other employees.

The candidate's answer should emphasize:

Ability to explain complex technical features
Basic to advanced knowledge of various Python features
Demonstrated experience using both shallow and deep copy within Python

Here's an example of a good answer to this question:

Example:

"Deep copy stores values that have already previously been copied. It also doesn't copy any reference pointers to certain objects. It'll reference an object, which leads the new object that's pointed by a different object to be stored as well. Since it makes copies for each object that's been called, deep copy slows down program execution. Shallow copies are different because they're used when a new instance type is created and keeps the copy values in a new instance. Since it doesn't make as many copies as deep copy, shallow copy's program execution is much faster."

Ready to get started? Post a Job