40 Most Asked Python Interview Questions

40 Most Asked Python Interview Questions
40 Most Asked Python Interview Questions

Python is the most used language in top companies such as Intel, IBM, NASA, Pixar, Netflix, Facebook, JP Morgan Chase, Spotify, and many more because of its performance and its powerful libraries. Here, you will come across some of the most frequently asked questions about Python in job interviews in various fields. Our Python interview questions for both experienced professionals and freshers will help you in your interview preparation. Let us take a look at some of the most popular and significant Python programming interview questions and answers.

40 Most Asked Python Interview Questions

1. Explain Python?

Python is a highly comprehensive, interactive & object-oriented scripting language. It is specifically developed with the purpose of making content highly readable among the surfers.

2. What are distinct features of python?

The distinct features of python are as follows:

  • Structured and functional programming is supported.
  • It can be compiled to byte-code for creating large applications
  • Develops high-level dynamic data types

3. What is pythonpath?

A pythonpath tells the python interpreter to locate module files that can be imported into program. It includes python source library directory ad source code directory.

4. Can be preset pythonpath?

Yes, we can preset pythonpath as a python installer.

5. Why do we use pythonstartup environment variable?

We use python startup environment variable because it consists of the path in which initialization file carrying python source code can be executed to start the interpreter.

6. What is PYTHONCASEOK environment variable?

PYTHONCASEOK environment variable is called in windows with the purpose to direct python to find the first case insensitive match in an import statement.

7. What are supported standard data types in python?

The supported standard data types are as follows

  • List
  • Number
  • String
  • Dictionary
  • Tuples

8. Define Tuples in Python?

Tuple is a collection of Python objects much like a list. The sequence of values stored in a tuple can be of any type, and they are indexed by integers. Tuples is a sequence data type in python. The number of values in tuples are separated by commas.

9.What are positive and negative indices?

In the positive indices, applied search begins from left to right. In negative indices search begins from right to left.

10. What can be the length of the identifier in python?

The length of the identifier in python can be of any length. The longest identifier will violate from PEP – 80 and PEP – 20.

11. Define pass statement in python?

A pass statement in python is used when we cannot decide what to do in our code, but we must type something for making syntactically correct.

12. What are the limitations of python?

There are certain limitations of python:

  • It has design restrictions
  • It is slower when compared with C and C++
  • It is inefficient in mobile computing
  • It consists of an undeveloped database access layer

13. Can we reverse a list in python?

Yes, we can reverse a list in python using a reverse method. The code can be depicted as:

def reverse(s):
    str = ""
    for i in s:
        str = i + str


return str

14. Why we need a break in python?

Break helps in controlling the python code by breaking the current loop from execution and transfer the control to the next block.

15. Why do we need a continue in python?

A continue in python helps in controlling python loop but by making jumps to the next iteration of loop without exhausting it.

16. Can we use a break and continue together?

Break and continue can be used together in python. The break will stop the current loop form execution, while continue will jump to the next iteration of loop

17. Does python support an intrinsic do while loop?

No, Python doesn’t have do-while loop. But we can create a program like this. The do while loop is used to check condition after executing the statement. It is like while loop but it is executed at least once.

18. How many ways can be applied for applying reverse string?

There are five ways in which reverse string can be applied which includes following:

  • Loop
  • Recursion
  • Stack
  • Extended Slice Syntax
  • Reversed

19. What is the purpose of relational operators in python?

The purpose of relational operators in python is to compare values.

20. What are assignment operators in python?

The assignment operators in python can help in combining all the arithmetic operators with the assignment symbol.

21. Why do we need membership operators in python?

We need membership operators in python with the purpose to confirm if the value is a member in another or not.

22. What are different stages of the life cycle of a thread?

The different stages of the life cycle of a thread can be studied as follows:

Stage 1: Creating a class where we can override run method of thread class.

Stage 2: We make a call to start() on the new thread. The thread is taken forward for scheduling purposes.

Stage 3: Execution takes place where thread starts execution, and it reaches running state.

Stage 4: Thread wait until calls to methods including join() and sleep() takes place.

Stage 5: After waiting or execution of thread, the waiting thread is sent for scheduling.

Stage 6: Running thread is done by executing the terminates and reaches the dead state.

23. What is dictionary in python?

A dictionary in python is an unordered collection of data values such as map. Dictionary holds key : value pair.

24. Explain how it is possible to Get the process of compilation and linking in python?

In order to ccompile new extensions without any error, compiling and linking is used in python. Linking indicates only when compilation is complete. In case of dynamic loading, process of compilation and linking depends on style that is provided with the concerned system.

25. What is flask and what are the benefits?

Flask is a web micro frame work for python with Jinja 2 and Werkzeug as its dependencies. As such, it has some notable advantages:

  • Flask has little to no dependencies on external libraries.
  • Features an inbuilt development server and a fast debugger.

26. What is map function used for in python?

Map in Python is a function that works as an iterator to return a result after applying a function to every item of an iterable (tuple, lists, etc.). It is used when you want to apply a single transformation function to all the iterable elements. The iterable and function are passed as arguments to the map in Python.

27. What is pickling and unpickling in python?

The pickle module in python allows accepting any object and then converting it into a string representations. The reverse process of pickling is known as unpickling i.e retrieved original python objects from a stored string represenation.

28. Whenever python exists, all memory isn’t deallocated. Why is it so?

Upon exiting, python’s built-in effective cleaning mechanism comes into play and try to deallocate or destroy every other object. This is because it is not possible to deallocate those portions or memory that are reserved by the C library.

29. Write a program in python for getting indices of N maximum values in NumPy array.

import numpy as np
arr = np.array([1, 3, 2, 4, 5])
print(arr.argsort()[-3:][::-1])
[4 3 1]

30. Write code to show randomization items of a list in place in python along with output?

import random
lis1 = [15,12,48,19,63]
print("The original list is: ",lis1)
random.shuffle(lis1) #shuffle method
print("The shuffled list is: ",lis1)
The original list is:  [15, 12, 48, 19, 63]
The shuffled list is:  [19, 48, 12, 63, 15]

31. What is lambda function?

An anonymous function is known as a lambda function. This function can have only one statement but can have any number of parameters.

x = lambda a, b : a * b
print(x(5, 6))

32. What are python decorators?

A specific change made in python syntax to alter functions easily are termed as python decorators.

33. Differentiate between list and tuple

Tuple is not mutable and it can be hashed e.g. Key for dictionaries. On the other hand, lists are mutable.

34. How are arguments passed in python? By Value or by reference.

Python’s argument passing model is neither “Pass by Value” nor “Pass by Reference” but it is “Pass by Object Reference

35. What are built-in types provided by python?

Mutable built-in types:

  • Lists
  • Sets
  • Dictionaries

Immutable built-in types:

  • Strings
  • Numbers
  • Tuples

36. How a file is deleted in python?

The file can be deleted by either of these commands:

os.remove(filename)
os.unlink(filename)

37. What are python modules?

A file containing python code like functions and variables is a python module. A python module is an executable file with a .py extension. Python has 200+ built-in modules some of which are:

  • os
  • sys
  • math
  • datetime
  • JSON

38. What is // Operator and what is its uses?

The // is a floor division operator used for dividing two operands with result as a quotient displaying digits before decimal point.

For Instance 10 // 5 = 2

and 10.0 // 5.0 = 2.0

39. What is split function used for?

The split function breaks the string into shorter strings using the defined separator. It returns the list of all words present in the string.

40. Is python a case-sensitive language?

Yes, python is a case-sensitive language.