41 interview questions on Python for developers (2026)

Hard

8 votes2378 runs

2 comments

Why is the output of the following code undefined? ``` def f(n): return n + 1 f(n) ```

Back-end developer

python

scope

Antoine Brennerat Dec 2, 2021

Hard

7 votes2371 runs0 comment

What is the output of the following code? ``` import asyncio async def read_data(): with open('data.txt', 'r') as f: data = f.read() return data async def main(): data = await read_data() print(data) if name == 'main': asyncio.run(main()) ```

Back-end developer

coroutines

event loop

Antoine Brennerat Dec 2, 2021

Hard

6 votes2380 runs

2 comments

Write a Python program to open a file in binary mode and write a string to it.

Back-end developer

python

file

binary

Antoine Brennerat Dec 2, 2021

Hard

5 votes2374 runs0 comment

In Python, what is the output of the following code? `valueA = 10; valueB = 10; valueA is valueB`

Back-end developer

python

boolean

Antoine Brennerat Dec 2, 2021

Hard

5 votes2371 runs0 comment

Create a list of 10 elements in Python

Back-end developer

list

python

Antoine Brennerat Dec 2, 2021

Hard

5 votes2362 runs0 comment

Python: Decorator that prevents the creation of an instance of a class

Back-end developer

decorators

inheritance

Antoine Brennerat Dec 2, 2021

Hard

5 votes2351 runs1 comment

Write a Python function that returns the sum of the first n integers.

Back-end developer

docstring

python

Anonymous authorat Dec 2, 2021

Hard

5 votes316 runs0 comment

Change the value of a nested list element in Python

Back-end developer

lists

nested lists

El Mehdiat Sep 4, 2023

Hard

4 votes2400 runs

1 comment

Write a Python function that returns a list of the first n numbers of the Fibonacci sequence.

Back-end developer

list comprehension

lambda

Antoine Brennerat Dec 2, 2021

Hard

4 votes2383 runs0 comment

What is the output of the following Python code? ``` G = '123' print(G + 1) ```

Back-end developer

python

type

Antoine Brennerat Dec 2, 2021

Hard

4 votes2379 runs

1 comment

Write a Python code that will wait for 40 seconds.

Back-end developer

python

async

Antoine Brennerat Dec 2, 2021

Hard

4 votes1349 runs

1 comment

In Python, which of the following statements are true about the keyword 'with':

Back-end developer

python

with

Anonymous authorat Dec 31, 2021

Hard

4 votes539 runs0 comment

Write a Python class with a method that takes two arguments.

Back-end developer

python

class

method

Anonymous authorat Sep 4, 2023

Hard

3 votes2413 runs0 comment

What is the output of the following code? ``` print("\u0041") ```

Back-end developer

python

strings

Antoine Brennerat Dec 2, 2021

Hard

3 votes2362 runs

2 comments

Explain the use of super in Python

Back-end developer

inheritance

super

Antoine Brennerat Dec 2, 2021

Hard

3 votes2349 runs

3 comments

Write a Python function that returns a copy of anotherlist with number appended to the end.

Back-end developer

functions

lists

Anonymous authorat Mar 28, 2023

Easy

3 votes2335 runs1 comment

Define a class method in Python

Back-end developer

python

class

Antoine Brennerat Dec 2, 2021

Hard

1 vote2415 runs

1 comment

What is the output of the following code? ``` def f(x): if x == 0: return 1 else: return f(x - 1) + f(x - 2) print(f(3)) ```

Back-end developer

python

variables

Antoine Brennerat Dec 2, 2021

Hard

1 vote2403 runs

1 comment

What is the value of valueA after the following code is executed? ``` valueA = 10 valueB = 20 valueA = valueB ```

Back-end developer

python

variables

Antoine Brennerat Dec 2, 2021

Hard

1 vote2384 runs

2 comments

Write a Python code that returns the first element of a list if the list is not empty, otherwise return None.

Back-end developer

python

list

Antoine Brennerat Dec 2, 2021

41 interview questions on Pythonfor developers (2026)

Test your technical skills before an interview of Python with 41 corrected questions. Beginner, Intermediate or Expert level.

Why is the output of the following code undefined? ``` def f(n): return n + 1 f(n) ```

What is the output of the following code? ``` import asyncio async def read_data(): with open('data.txt', 'r') as f: data = f.read() return data async def main(): data = await read_data() print(data) if name == 'main': asyncio.run(main()) ```

Write a Python program to open a file in binary mode and write a string to it.

In Python, what is the output of the following code? `valueA = 10; valueB = 10; valueA is valueB`

Create a list of 10 elements in Python

Python: Decorator that prevents the creation of an instance of a class

Write a Python function that returns the sum of the first n integers.

Change the value of a nested list element in Python

Write a Python function that returns a list of the first n numbers of the Fibonacci sequence.

What is the output of the following Python code? ``` G = '123' print(G + 1) ```

Write a Python code that will wait for 40 seconds.

In Python, which of the following statements are true about the keyword 'with':

Write a Python class with a method that takes two arguments.

What is the output of the following code? ``` print("\u0041") ```

Explain the use of super in Python

Write a Python function that returns a copy of anotherlist with number appended to the end.

Define a class method in Python

What is the output of the following code? ``` def f(x): if x == 0: return 1 else: return f(x - 1) + f(x - 2) print(f(3)) ```

What is the value of valueA after the following code is executed? ``` valueA = 10 valueB = 20 valueA = valueB ```

Write a Python code that returns the first element of a list if the list is not empty, otherwise return None.

41 interview questions on Pythonfor developers (2026)

Test your technical skills before an interview of Python with 41 corrected questions. Beginner, Intermediate or Expert level.

Why is the output of the following code undefined? ``` def f(n): return n + 1 f(n) ```

What is the output of the following code? ``` import asyncio async def read_data(): with open('data.txt', 'r') as f: data = f.read() return data async def main(): data = await read_data() print(data) if __name__ == '__main__': asyncio.run(main()) ```

Write a Python program to open a file in binary mode and write a string to it.

In Python, what is the output of the following code? `valueA = 10; valueB = 10; valueA is valueB`

Create a list of 10 elements in Python

Python: Decorator that prevents the creation of an instance of a class

Write a Python function that returns the sum of the first n integers.

Change the value of a nested list element in Python

Write a Python function that returns a list of the first n numbers of the Fibonacci sequence.

What is the output of the following Python code? ``` G = '123' print(G + 1) ```

Write a Python code that will wait for 40 seconds.

In Python, which of the following statements are true about the keyword 'with':

Write a Python class with a method that takes two arguments.

What is the output of the following code? ``` print("\u0041") ```

Explain the use of super in Python

Write a Python function that returns a copy of anotherlist with number appended to the end.

Define a class method in Python

What is the output of the following code? ``` def f(x): if x == 0: return 1 else: return f(x - 1) + f(x - 2) print(f(3)) ```

What is the value of valueA after the following code is executed? ``` valueA = 10 valueB = 20 valueA = valueB ```

Write a Python code that returns the first element of a list if the list is not empty, otherwise return None.

What is the output of the following code? ``` import asyncio async def read_data(): with open('data.txt', 'r') as f: data = f.read() return data async def main(): data = await read_data() print(data) if name == 'main': asyncio.run(main()) ```