Python Developer Freshers Top Interview Questions and Answers Part 1

Python Developer Freshers Top Interview Questions:

1. What is Python?
   • Answer: Python is a high-level programming language known for its simplicity and readability. It’s widely used in various fields such as web development, data science, artificial intelligence, etc.
2. What are the key features of Python?
   • Answer: Python’s key features include simplicity, readability, versatility, portability, and an extensive standard library.
3. Explain the differences between Python 2 and Python 3.
   • Answer: Python 3 is the latest version of Python and is not backward compatible with Python 2. Python 3 focuses on fixing various inconsistencies and improving Unicode support.
4. What are the different data types in Python?
   • Answer: Python supports various data types including int, float, str, list, tuple, dict, set, bool, etc.
5. How do you comment in Python?
   • Answer: In Python, you can use the # symbol for single-line comments and triple quotes (''' or """) for multi-line comments.
6. Explain Python’s Indentation.
   • Answer: Python uses indentation to define code blocks instead of braces. Consistent indentation is crucial for Python’s syntax and readability.
7. What is PEP 8?
   • Answer: PEP 8 is the style guide for Python code. It outlines conventions for writing readable and maintainable Python code.
8. How do you declare a variable in Python?
   • Answer: Variables in Python can be declared simply by assigning a value to them, like x = 5.
9. What is a tuple in Python?
   • Answer: A tuple is an immutable sequence of elements, typically used to store heterogeneous data.
10. What is a list in Python?
    • Answer: A list is a mutable sequence of elements, allowing for dynamic changes to its contents.
11. How do you create a function in Python?
    • Answer: You can create a function in Python using the def keyword followed by the function name and parameters.
12. Explain the difference between == and is in Python.
    • Answer: == checks for equality of values, while is checks for object identity.
13. What is the use of pass statement in Python?
    • Answer: The pass statement is a null operation used as a placeholder to maintain syntactic structure.
14. What is a dictionary in Python?
    • Answer: A dictionary is an unordered collection of key-value pairs, where each key is unique.
15. How do you iterate over a list in Python?
    • Answer: You can use a for loop to iterate over a list, like for item in my_list:.
16. Explain the use of __init__ method in Python.
    • Answer: The __init__ method is a constructor in Python classes, used to initialize object attributes.
17. What is a module in Python?
    • Answer: A module is a file containing Python code, typically containing functions, classes, and variables.
18. How do you import a module in Python?
    • Answer: You can import a module using the import keyword, like import my_module.
19. What is the purpose of the if __name__ == "__main__": statement?
    • Answer: This statement allows a Python script to be used both as a standalone program and as a module in other programs.
20. What is a lambda function in Python?
    • Answer: A lambda function is an anonymous function defined using the lambda keyword.
21. How do you handle exceptions in Python?
    • Answer: Exceptions in Python can be handled using try, except, finally, and else blocks.
22. What is the purpose of __doc__ attribute in Python?
    • Answer: The __doc__ attribute stores the docstring of a Python object, providing documentation.
23. What is list comprehension?
    • Answer: List comprehension is a concise way of creating lists in Python using a single line of code.
24. Explain the use of super() in Python.
    • Answer: super() is used to call methods from the parent class in a derived class.
25. What is the purpose of *args and **kwargs in Python?
    • Answer: *args and **kwargs allow functions to accept variable numbers of arguments and keyword arguments respectively.
26. What is the __str__ method used for in Python?
    • Answer: The __str__ method is used to return a string representation of an object.
27. What is the purpose of __repr__ method?
    • Answer: The __repr__ method returns a string representation of the object that can be used to recreate the object.
28. How do you open and close a file in Python?
    • Answer: You can open a file using the open() function and close it using the close() method.
29. What is the purpose of with statement in Python?
    • Answer: The with statement is used to ensure proper acquisition and release of resources.
30. Explain the difference between append() and extend() methods in Python lists.
    • Answer: append() adds its argument as a single element to the end of a list, while extend() takes an iterable and adds each element to the list individually.
31. What is a generator in Python?
    • Answer: A generator is a function that returns an iterator, allowing you to iterate over a sequence of items.
32. How do you define a class in Python?
    • Answer: You can define a class in Python using the class keyword followed by the class name and a colon.
33. What is inheritance in Python?
    • Answer: Inheritance allows a class to inherit attributes and methods from another class.
34. Explain the concept of method overriding in Python.
    • Answer: Method overriding occurs when a subclass provides a specific implementation of a method that is already defined in its superclass.
35. What is the purpose of self in Python?
    • Answer: self is a reference to the current instance of the class, allowing you to access its attributes and methods.
36. How do you create a virtual environment in Python?
    • Answer: You can create a virtual environment using the venv module by running python -m venv myenv.
37. What is the purpose of pip in Python?
    • Answer: pip is a package manager for Python, used to install and manage Python packages.
38. Explain the use of decorators in Python.
    • Answer: Decorators are functions that modify the behavior of other functions or methods.

39. What is the purpose of the __init__.py file in Python?

• Answer: The __init__.py file is used to define a package in Python. It can be empty or contain initialization code that runs when the package is imported.

40. Explain the difference between deepcopy() and copy() methods in Python.

• Answer: copy() creates a shallow copy of an object, meaning it duplicates the object but not its nested objects. deepcopy() creates a deep copy, duplicating the object and all of its nested objects recursively.

41. How do you handle file reading and writing in Python?

• Answer: You can open files using the open() function in Python. To read from a file, use the read() method or iterate over the file object. To write to a file, use the write() method.

42. Explain the purpose of the pickle module in Python.

• Answer: The pickle module in Python is used for serializing and deserializing Python objects. It allows you to save and load Python objects to and from files.

43. What is the purpose of the sys module in Python?

• Answer: The sys module provides access to some variables used or maintained by the Python interpreter, and to functions that interact strongly with the interpreter.

44. How do you handle JSON data in Python?

• Answer: Python provides the json module for encoding and decoding JSON data. You can use json.loads() to parse JSON from a string, and json.dumps() to serialize a Python object to a JSON formatted string.

45. Explain the purpose of the os module in Python.

• Answer: The os module provides a way of using operating system dependent functionality. It allows you to interact with the operating system, such as navigating the file system, working with files and directories, etc.

46. What is a set in Python?

• Answer: A set is an unordered collection of unique elements in Python. It is useful for tasks like removing duplicates from a sequence and performing set operations like union, intersection, etc.

47. How do you remove duplicates from a list in Python?

• Answer: You can remove duplicates from a list by converting it to a set using the set() function, then converting it back to a list.

48. Explain the purpose of the enumerate() function in Python.

• Answer: The enumerate() function is used to loop over an iterable and return both the index and the value of each item in the iterable.

49. What is the purpose of the __call__ method in Python?

• Answer: The __call__ method enables an object to be called as if it were a function. It allows instances of a class to be called like a function.

50. How do you check if a key exists in a dictionary in Python?
    • Answer: You can use the in keyword to check if a key exists in a dictionary. For example, if key in my_dict: will return True if key exists in my_dict, and False otherwise.