45 Python Interview Questions for Freshers with Answers

Python has become one of the most popular programming languages for a wide range of applications, from web development to machine learning. If you are a fresher looking to start your career in Python, you need to be prepared to answer some basic and advanced Python interview questions. In this blog post, we will cover 45 Python interview questions with answers for freshers to help you prepare for your upcoming Python interview.

1. What is Python, and what are its advantages?

Answer: Python is a high-level, interpreted, general-purpose programming language that emphasises code readability and simplicity. Python's advantages include easy-to-learn syntax, a wide range of libraries and frameworks, cross-platform compatibility, and a large and supportive community.

2. What are the different data types in Python?

Answer: The different data types in Python include integers, floating-point numbers, complex numbers, strings, Boolean values, and lists, tuples, and dictionaries.

3. What is a tuple, and how is it different from a list?

Answer: A tuple is a collection of ordered, immutable elements, whereas a list is a collection of ordered, mutable elements. Tuples are typically used to represent data that should not be changed, whereas lists are used for data that needs to be updated or modified.

4. What is a dictionary in Python?

Answer: A dictionary in Python is a collection of key-value pairs that can be accessed using the keys. Dictionaries are unordered, mutable, and can contain elements of any data type.

5. What is a module in Python?

Answer: A module in Python is a file containing Python code that can be imported into another Python program. Modules are used to organize and reuse code.

6. What is the difference between range and xrange?

Answer: In Python 2, range() generates a list of numbers, whereas xrange() generates an iterator object that returns the numbers on-the-fly, which is more memory efficient. In Python 3, range() works like xrange() in Python 2.

7. What is the difference between a local and global variable in Python?

Answer: A local variable is defined inside a function and can only be accessed within that function. A global variable is defined outside of any function and can be accessed anywhere in the program.

8. What is the purpose of the init method in Python?

Answer: The init method is used to initialize an object when it is created. It is called automatically when an object is instantiated and can be used to set the initial state of the object.

9. What is the difference between a function and a method in Python?

Answer: A function is a block of code that can be called from anywhere in the program, whereas a method is a function that is associated with an object and can only be called on that object.

10. What is a lambda function in Python?

Answer: A lambda function is a small, anonymous function that can take any number of arguments but can only have one expression. Lambda functions are typically used for short, one-off functions that are not needed elsewhere in the program.

11. What is a decorator in Python?

Answer: A decorator in Python is a function that takes another function as input and extends its behavior without modifying its source code. Decorators can be used to add functionality to existing functions, such as logging or caching.

12. What is the difference between the append() and extend() methods for lists in Python?

Answer: The append() method adds a single element to the end of a list, whereas the extend() method adds a sequence of elements to the end of a list.

13. What is the difference between a shallow copy and a deep copy in Python?

Answer: A shallow copy creates a new object that points to the same memory location as the original object, whereas a deep copy createsa completely new object with its own memory space. Changes made to the original object will not affect the shallow copy, but changes made to the original object may affect the deep copy.

14. What is a generator in Python?

Answer: A generator in Python is a function that uses the yield keyword to return an iterator object. The generator generates values on-the-fly, rather than storing them all in memory at once.

15. What is a set in Python?

Answer: A set in Python is an unordered collection of unique elements. Sets are mutable and can be modified using methods such as add() and remove().

16. What is the difference between a list and a tuple in Python?

Answer: A list is a collection of ordered, mutable elements, whereas a tuple is a collection of ordered, immutable elements. Lists are typically used for data that needs to be updated or modified, whereas tuples are used to represent data that should not be changed.

17. What is a string in Python?

Answer: A string in Python is a sequence of characters enclosed in quotation marks. Strings are immutable, meaning they cannot be changed once they are created.

18. What is the difference between a while loop and a for loop in Python?

Answer: A while loop executes as long as a condition is true, whereas a for loop iterates over a sequence of elements. While loops are typically used when the number of iterations is unknown, whereas for loops are used when the number of iterations is known.

19. What is the purpose of the break and continue statements in Python?

Answer: The break statement is used to exit a loop early, whereas the continue statement is used to skip the current iteration of a loop and move on to the next iteration.

20. What is a class in Python?

Answer: A class in Python is a blueprint for creating objects. It defines the properties and methods that the objects will have.

21. What is inheritance in Python?

Answer: Inheritance in Python allows a subclass to inherit properties and methods from a superclass. This allows for code reuse and promotes a more efficient and organized coding process.

22. What is polymorphism in Python?

Answer: Polymorphism in Python allows for the same method to have different implementations in different classes. This allows for more flexible and versatile code.

23. What is a try-except block in Python?

Answer: A try-except block in Python is used to catch and handle exceptions. The try block contains the code that may raise an exception, and the except block contains the code that will handle the exception if it is raised.

24. What is a module in Python?

Answer: A module in Python is a file containing Python code that can be imported into another Python program. Modules are used to organize and reuse code.

25. What is the purpose of the name attribute in Python?

Answer: The name attribute in Python is used to determine if a module is being imported or run as the main program. If the module is being imported, the name attribute will be set to the name of the module. If the module is being run as the main program, the name attribute will be set to "main".

26. What is PEP 8, and why is it important in Python?

Answer: PEP 8 is a set of guidelines for writing Python code that promotes consistency, readability, and maintainability. It is important in Python because it helps make code more easily understood by other developers and reduces the likelihood of errors and bugs.

27. What is a virtual environment in Python?

Answer: A virtual environment in Python is a self-contained directory that contains its own Python installation and packages. It allows for the isolation of dependencies between projects and helps prevent version conflicts.

28. What is a package in Python?

Answer: A package in Python is a way of organizing related modules into a single directory hierarchy. It allows for the grouping and reuse of related code.

29. What is pip in Python?

Answer: pip is a package manager for Python that is used to install and manage Python packages. It can be used to install packages from the Python Package Index (PyPI) and other sources.

30. What is the difference between a module and a package in Python?

Answer: A module is a single file containing Python code, whereas a package is a directory containing related modules and other packages. Modules are typically used to organize code within a project, whereas packages are used to organize and distribute code between projects.

31. What is a lambda function in Python?

Answer: A lambda function in Python is a small, anonymous function that can have any number of arguments, but can only have one expression. Lambda functions are often used as a shorthand for simple functions and can be passed as arguments to higher-order functions.

32. What is the difference between a local variable and a global variable in Python?

Answer: A local variable is a variable that is defined inside a function and can only be accessed from within that function, whereas a global variable is a variable that is defined outside of any function and can be accessed from anywhere in the code.

33. What is a decorator in Python?

Answer: A decorator in Python is a function that takes another function as input and returns a new function with added functionality. Decorators are often used to modify the behavior of functions without changing their code directly.

34. What is the difference between a method and a function in Python?

Answer: A method is a function that is associated with an object, whereas a function is not associated with any object. Methods are typically called on objects, whereas functions are called independently.

35. What is the difference between the read() and readline() methods of a file object in Python?

Answer: The read() method of a file object reads the entire contents of a file as a single string, whereas the readline() method reads a single line from the file. The read() method is typically used for reading small files, whereas the readline() method is used for reading larger files line-by-line.

36. What is a dictionary in Python?

Answer: A dictionary in Python is an unordered collection of key-value pairs. Each key in the dictionary is unique, and the values can be any Python object.

37. What is the difference between an instance method, a class method, and a static method in Python?

Answer: Instance methods operate on an instance of a class and can access instance-specific data. Class methods operate on the class itself and can access class-level data. Static methods do not depend on either the instance or the class and are typically used for utility functions.

38. What is the difference between the "is" and "==" operators in Python?

Answer: The "is" operator in Python checks if two objects are the same object in memory, whereas the "==" operator checks if two objects have the same value.

39. What is the purpose of the "yield" keyword in Python?

Answer: The "yield" keyword in Python is used to define a generator function, which can return a value and then resume execution later from the same point. This allows generators to generate a sequence of values on demand rather than generating all of the values at once.

40. What is the purpose of the "map" function in Python?

Answer: The "map" function in Python is used to apply a function to each element of an iterable and return a new iterable containing the results.

41. What is the purpose of the "filter" function in Python?

Answer: The "filter" function in Python is used to apply a function to each element of an iterable and return a new iterable containing only the elements for which the function returned True.

42. What is the purpose of the "pop" method in Python?

Answer: The "pop" method in Python is used to remove and return the last element of a list. It can also be used with an index to remove and return a specific element from the list.

43. What is the purpose of the "sort" method in Python?

Answer: The "sort" method in Python is used to sort the elements of a list in place. It can also take arguments to customize the sorting behavior.

44. What is a closure in Python?

Answer: A closure in Python is a function object that has access to variables in its enclosing lexical scope, even when the function is called outside of that scope.

45. What is the purpose of the "assert" statement in Python?

Answer: The "assert" statement in Python is used to check that a condition is true, and if it is not, it raises an AssertionError with an optional error message.

We hope these 45 Python interview questions and their answers will help you prepare for your next Python interview. Remember that it's not just about knowing the answers but also understanding the concepts behind them. Good luck!