In this collection, I have chosen 60+ mostly asked Python interview questions and answers, which will surely help you to get success in interviews.
1. What is Python?
Python is a high-level, interpreted, general-purpose programming language. It is one of the most popular programming languages, and it has been around for over 25 years. It is an open-source language.
2. Who created Python?
Guido van Rossum developed Python in 1991.
3. What type of language is Python?
Python is a high-level, interpreted, object-oriented programming language. It is also the perfect language for those who are just beginning to learn coding.
4. What are the benefits of using Python?
Python offers many benefits for web development, such as its object-oriented design that makes it easy to develop modular applications. Python also has excellent library support, so developers can use built-in libraries or third-party packages to make development quicker and easier. It is also fast and efficient when compared to other languages, making it ideal for large-scale applications.
5. What are some key features of Python?
-Object-oriented programming.
-A large standard library.
-Support for modules and packages.
-Dynamic typing and binding.
-Strong integration and text processing capabilities.
6. What are some advantages of using Python?
The biggest advantage of using Python is its large variety of modules and packages that are available. Python has a extensive library for almost all tasks imaginable. It is also very easy to get into and the syntax of the language is very clear and easy to read. It is also a popular language for scripting, automation, and web development.
7. Why Python is best language?
Python is a versatile language with many benefits such as:
♦ It is easy to learn.
♦ It is highly scalable.
♦ It supports multiple programming paradigms.
♦ It provides extensive libraries and modules for almost any task.
♦ It can interact with most other programming languages.
♦ Python also allows fast prototyping and productive development.
8. How python is different from other programming languages?
Interpreted : Python is an interpreted language, meaning that it is executed at runtime and does not require a separate compilation step. This makes it easier to debug and makes it faster to develop with. Additionally,
Object-oriented : Python is an object-oriented language, meaning that it is organized around objects, which can contain both data and methods. This makes it more modular and easier to work with large codebases.
Open-source : Python is open-source and free, meaning that anyone can use it without having to pay for a license.
9. What is the structure of Python?
Python is a high-level, interpreted, object-oriented programming language. It is structured around the following four main components:
(i) Data and Expressions: This is the foundation of the language and involves working with data and writing expressions, which can be used to manage and manipulate information.
(ii) Control and Logic: Control statements, such as if, while, and for, enable us to construct logical programs and decide when and how to make decisions or perform tasks.
(iii) Functions and Modules: Functions are pieces of code that can be reused to performing specific tasks. Modules are collections of functions and variables that may be imported into other programs.
(iv) Classes and Objects: Classes can be used to define user-defined data types and objects. Objects are instances of classes and can be used to store data and define behavior.
10. What are the different data types in Python?
Python supports numbers(integer, long, float, complex), strings, lists, tuples, and dictionaries datatypes.
11. What is the syntax of Python?
Python syntax is based upon the English language and the structures of other languages, such as C and Perl. The basis of Python is composed of indented blocks, keywords, and expressions.
12. What is PEP 8?
PEP 8 is a style guide used for programming in Python. It was designed to make the writing of code consistent and more readable.
13. What are the differences between Python and Java?
Python and Java are two different programming languages. Python is a high-level, interpreted language, whereas Java is compiled and more verbose. Python is easier to learn, while Java has more features. Python is better for scripting, whereas Java is better for large applications. Java is statically typed, but Python is dynamically typed.
14. Which version of Python should I use?
Python 3 is the recommended version to use. All new features and libraries are being developed for Python 3, and most new projects are built in it. Python 2 should only be used for legacy projects.
15. What is a list and a tuple in Python?
A list is a mutable data type in Python, where elements can be added, removed or modified. A tuple is an immutable data type in Python, where elements cannot be changed.
16. How do you create an array in Python?
An array in Python is created with the array.array() method. For example:-
num_array = [1, 2, 3, 4, 5,6,7]
str_array = [“Code“, “Revise“, “Learn“,”Programming”]
17. What is the use of *args and **kwargs?
*args and **kwargs are special syntax in Python used to pass a variable number of arguments to a function. *args is used to pass a non-keyworded, variable-length argument list, and **kwargs is used to pass a keyworded, variable-length argument list.
18. What are the main data structures in Python?
The main data structures in Python are lists, dictionaries, tuples, sets, and strings.
19. What is the syntax for declaring a variable in Python?
In Python, a variable is declared with the assignment operator (=). For example,
my_variable = 10
20. What are the control flow statements in Python?
Python has the following control flow statements: if/else, while, for, try/except, break, continue, pass.
21. What is a functions in Python?
A Python function is a section of code that completes a certain job. It is defined using the def keyword, and can accept arguments and return a value.
22. What is list and tuple in Python?
Lists are variable-length objects, allowing for modification and insertion of items, whereas tuples are fixed-length objects and therefore they are immutable.
23. How do you execute a Python script from the command line?
You can execute a Python script from the command line by typing python script_name.py.
24. Describe PEP 8 and why is it important?
PEP 8 is the Python coding style guide. It helps ensure consistency, clarity, and maintainability of code.
25. What is a dictionary in Python?
A dictionary in Python is a type of collection that stores elements in key-value pairs. It is an unordered associative array of values, and is optimized for retrieving data quickly.
26. What is a namespace in Python?
A namespace in Python is a system that helps to keep track of all the names used in a program by assigning each name a unique name. This prevents name clashes between different objects and functions in a program. Each object in Python has its own namespace.
27. How is memory managed in Python?
In Python, memory is managed by the Python Memory Manager. The memory manager allocates and reclaims memory from the underlying operating system, handling the memory pool of objects used by the interpreter.
28. What is a lambda function in Python?
A lambda function is an anonymous function in Python that is used to create small, one-time and anonymous functions. These functions contain only one expression, which is used to evaluate and return a value. Lambda functions can be used anywhere a function is required, such as with filter(), map(), and reduce().
29. How do you debug a Python program?
Python offers several debugging options, such as the interactive debugger (pdb), or using external debugging tools like PyCharm, WinPDB, and Pydev. The interactive debugger allows you to step through and debug your code line by line. Other debugging tools provide graphical interfaces for greater control and debugging capability.
30. What are the benefits of using Python over other programming languages?
Python is an easy to learn, versatile, and popular programming language. It is used in a variety of industries, ranging from web development to data science. It supports multiple paradigms, such as object oriented, functional, procedural, and aspect-oriented programming. It is also open source, and has strong support from the community and a large set of libraries. All these factors make Python popular amongst developers.
31. How is Python interpreted?
Python is an interpreted language, meaning that the written code is not compiled into machine-readable code before being run. When the Python interpreter reads the source code, it converts each line into a byte of code, which is then translated into the native machine language.
32. What is the main use of Python?
Python is a general-purpose programming language used for web development, software development, scripting, artificial intelligence, data science, statistical analysis, and more. It can be used to build simple or complex applications, from web applications to network servers and desktop applications.
33. What are the built-in types of python?
Some of the built-in types in Python are strings, Boolean, numbers, lists, sets, tuples, and dictionaries.
34. How can you make a Python script executable on Unix?
To make a Python script executable on Unix, you can add the following line at the top of the script: #!/usr/bin/env python.
35. What is the use of ‘self’ keyword in Python?
The self keyword is used to refer to the current instance of a class or an object in Python. It is often used as an argument in the class methods to refer to the current instance of the class. This allows the method to access and update the class instance internal states using the self keyword.
36. What is polymorphism?
Polymorphism in Python is the same definition as it is in other programming languages, it is the ability to use different objects with the same code. This means that a single code or programming language can be used to define variables or objects of multiple types, including strings, integers, floats, and booleans.
37. What is slicing in Python?
Slicing in Python is a technique for retrieving portions of data from a sequence. The slicing operator (:) is used to do this.
38. How is memory managed in Python?
Python memory management is taken care of by the Python memory manager. The memory manager is responsible for allocating and releasing memory as needed.
39. What is a decorator in Python?
A decorator in Python is a specific type of function (or class) that takes another function (or class) as an argument and returns a modified function (or class) as its result. Decorators are used to extend and modify the behavior of existing functions and classes in Python without having to permanently modify the source code.
40. What is the difference between deep and shallow copy in Python?
A deep copy creates a new object and recursively copies the contents of the original object into it, meaning that if the original object contains other objects like lists or dictionaries, those will also be copied.
A shallow copy creates a new object and copies the reference pointers of the original object. This means that if the original object contains any other objects, references to those objects will still be in the new object, but the new object itself will not contain copies of the other objects.
41. What are some popular applications of Python?
Python is widely used in web development, machine learning, game development, scientific computing, and data science. It is also popular for the automation of mundane tasks, scripting, GUI-based applications, and a lot more.
42. Is Python interpreted or compiled?
Python is an interpreted language. This means that it is not directly compiled to machine code, but instead executed by an interpreter.
43. How is memory managed in Python?
Memory management in Python is managed by the Python interpreter itself. Python has private heaps which manages the objects and memory allocations. Python’s allocation of heap space is done when an object is created. Python also uses a garbage collector to periodically clean up unused memory and free it up for use.
44. What are Python decorators?
Python decorators are special functions that are used to wrap other functions and modify their behavior. They are used to add extra functionality to an existing function without changing its source code.
45. What is the NumPy in Python?
NumPy is a powerful Python library used for scientific computing, data analysis and manipulation. It is used for advanced mathematical functions, linear algebra, random number capabilities and array/matrix manipulation. NumPy provides a large collection of high-level mathematical functions to operate on these arrays or matrices.
46. What are some of the main functions in Python?
Python has a number of built-in functions such as print(), abs(), min(), max(), len(), type(), int() and float(). Additionally, there are a large number of third-party functions available as well. These functions are used to help develop and debug code more quickly and efficiently.
47. What is local variable and global variable?
Local variables are those that are declared and used inside a function. Global variables are those that are declared outside of a function and are available for use throughout the program.
48. What is a package in Python?
A package in Python is a container that collects modules together. Packages are used to organize related Python modules and provide a single namespace, meaning any object with the same name present in different packages can be used without any conflict. A package is represented by a directory with __init__.py file that contains the code for the package initialization.
49. What is pickling and unpickling?
Pickling and unpickling are Python processes that allow objects to be converted into a character stream and saved to files or transmitted over a network. Pickling is the process of serializing an object into a byte stream, while unpickling is the opposite process of loading the byte stream back into an object.
50. What is the purpose of the split() method in Python?
The split() method in Python is used to divide a string into a list of substrings, with each substring representing a word. It splits the string on a specified separator and returns a list of substrings.
51. What is the difference between copying and cloning in Python?
Copying is a shallow operation where the contents of one object is simply copied into a new object. Cloning is a deep operation where a new object is created with an exact copy of the contents of the original object. Copying does not make a deep copy of an object, while cloning does.
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