Common Interview Questions for Your Next Python Job

Learning Python is a great option – it’s one of the most in-demand programming languages. If you are about to start your career with Python, you’ll have to prepare yourself for job interview questions. In this article, I will help you with this task.

If you don’t want to be surprised during a recruitment process, give yourself plenty of time to prepare for a Python job interview. I recommend first reviewing your knowledge with the help of one of our online courses, like the free Python Basics: Part 1.

Why Learn Python?

Python has been around since 1989, when its creator, Guido van Rossum, came up with the fundamentals of a language so popular nowadays. If you are curious where the name Python comes from and how this language was developing, read my article about its history.

Python is a comprehensive programming language. It can be used for task automation, web development, software development, machine learning, and data science. Python is also widely used in data analysis and data visualization.

Thanks to its simple syntax, Python is easy to learn. This comes in handy in non-tech positions; business analysts, marketing specialists, managers, and administrators can all profit from Python's versatility.

Learning Python gives you a lot of possibilities. Even if you are not entirely sure which industry you want to pursue, knowing Python opens up many interesting career paths. But what kind of Python knowledge do you need to have to ace a job interview?

Common Python Job Interview Questions

To prepare well for a Python job interview, it is important to practice a lot. Use multiple sources of knowledge to strengthen your skills. Talk to people who have landed Python jobs. Use the support of the Python community, even while you’re taking online courses like this Python Practice Set.

You should also review and prepare yourself for common Python questions, such as the ones below:

1.   Is Python a programming or scripting language?

Scripting is possible with Python, but it is considered a programming language.

It’s a good idea to explain the difference between scripting and programming to show that you understand the background. Programming languages include a set of instructions that return a specific output. Scripting languages are written to support scripts, which are written for a special runtime environment to automate execution of a specific action or function.

2.    What’s the difference between lists and tuples?

Lists and tuples are both built-in Python data types, but they have several differences. Lists are mutable (they can be changed) and tuples are immutable, which means they can’t be changed. Lists are slower than tuples and are created in square brackets [ ], whereas tuples are created in parentheses ( ).

You can read more about the difference in the article Python Lists, Tuples, and Sets: What’s the Difference?

3.   What is a Python library? Name some common Python libraries.

A Python library is a collection of related modules, or precompiled code that can be deployed in many different programs. Libraries make Python easier to use. They are also more convenient, because you don’t need to write the same code multiple times.

Some of the most popular Python libraries include:

• TensorFlow, which is used in machine learning and neural networks.
• NumPy, which contains mathematical functions and tools for working with arrays.
• SciPy, a scientific computation library that is based on NumPy.
• Pandas, which is used in data manipulation and analysis.
• Matplotlib, which is commonly used for making data visualizations.
• Keras, used for implementing neural networks.
• SciKit-Learn, another data analysis library.
• PyTorch, a machine learning framework.

To learn more, check out the article The Most Popular Python Libraries.

4.   What is a function argument? Give some examples.

An argument is a value that is sent to the function when it is called. The function performs some action on data and returns the result. In Python, there are 4 types of arguments:

• Optional arguments (which may or may not be explicitly defined) and default arguments, which are used if an optional argument is not provided.
• Keyword arguments (also called named arguments), which follow an identifier (e.g. flavor = “vanilla”).
• Positional arguments, which must be included in a specific order.
• Arbitrary arguments (*args and **kwargs), used when you have to pass an unknown number of arguments into a function.

5.   How would you copy an object in Python?

In Python, not all objects can be copied. But the copy.copy() or copy.deepcopy() methods can be used on some objects.

6.   Explain how the if statement works in Python.

An if statement is used for decision-making operations. It contains a block of code which will be followed only when the if condition is true. When the condition is false, either another optional statement runs  (the else statement) or the block of code inside the if is skipped. For example:

def main(): 
x,y =2,8
if(x < y):
	st=”x is less than y”
print(st)

if __name__ == ”__main__”:
	main()

7.   Write a Python program that checks how many capital letters are in a file.

with open("text.txt") as file:
    count = 0
    text = file.read()
    for i in text:
        if i.isupper():
            count += 1
    print(count)

Sometimes you will need to write this type of program as a one-liner, or a shortened piece of code. Check out these 10 Python one-liners for some inspiration

8.   What experience do you have working with Python?

This is another question your future boss will surely ask you. Be prepared to explain how you learned Python and how long you’ve been writing Python code. Describe examples of your projects. If you’ve created an application, show it and describe how you built it.

Also, be prepared to define your expectations and what you value in your job environment. Know what your plans are and how you want to develop as a Python professional.

To see more examples of Python questions and answers, check out this list of job interview questions.

Before the Job Interview

Now you know some questions that may appear during your Python job interview. I encourage you to practice answering these questions and writing code. Writing your own code is the best way to gain Python experience. To upgrade your skills, take one of our interactive online courses. They’ll help you gain knowledge, consolidate your skills, and track your learning progress.

If you have some Python coding experience, you can start with the Python Basics Practice Set. It’s full of beginner-friendly exercises which will let you learn and have fun at the same time. For those who know that they want to develop Python skills in data science, our Introduction to Python for Data Science will help them get a fast and effective start.

If you want more, try Python Practice: Word Games. This training contains three thematic sections related to strings and words in Python. In the first part, you will implement a simple cipher in Python to code and decode words. In the second part, you will analyze the text of a famous Sherlock Holmes novel. In the last section, you will learn to implement functions for a Scrabble-type game.

None of these online courses require an IT background. You can start to learn from scratch, even if you know nothing about programming. You’ll learn systematically and check your progress with quizzes included in the training path. You can also contact the learning community to discuss any problems you might have.

Learning Python will help you to find your dream job, but it is also a way to keep your brain in good shape. After all, learning Python makes you smarter.

Python Jobs and Your Future

Working with Python means you need to know it very well. The more skills and experience you have, the better your chance of succeeding at job interviews.

The IT industry is still growing and is looking for people who are eager to learn and develop professionally. But not only in the tech industry that Python is used; more and more business, data analysis, marketing, and management employees are using Python. And if you need more motivation, check out this article on Python job salaries

Learning Python and working with it opens up a really interesting professional life. Start today and reach for your dream job.