Top Python Interview Questions and Answers in 2023

Python is one of the most popular programming languages in the world because of its versatility and easy accessibility and is widely used across a variety of fields. As such, job interviews for Python programmers are becoming increasingly competitive. It is crucial to be familiar with the latest trends and updates in the language for candidates preparing for a Python interview in 2023. This article explores some of the top Python interview questions and answers in 2023 to help candidates prepare for their next interview and magnify their chances of landing their preferred Python job.

Top Python Interview Questions and Answers in 2023

Aspirants after pursuing Python Courses should be aware of all the questions that are asked during any Python job interviews. Some of the top Python interview questions and answers in 2023 according to different proficiency levels are discussed below. 

Top Python Interview Questions and Answers in 2023 - Beginner

Some of the best and most asked Python interview questions along with their answers at the beginner level are as follows - 

Ques. What is Python Programming language?

Ans. Python is a high-level, interpreted programming language that is used for a variety of applications such as web development, data analysis, machine learning, and more. It was developed by Guido van Rossum and released on February 20, 1991 and has since become one of the most popular programming languages in the world.

Ques. What are the advantages of using Python?

Ans. Being an open-sourced language, it is free to use and can be customised according to a wide variety of applications is one of the major advantages of using Python. Large standard library, readability and easy accessibility are some of its other advantages.

Ques. Define Scope.

Ans. In Python, a scope is a region of the program where a variable or function can be accessed and referenced. It defines the visibility and lifetime of a variable or function. There are two types of scope in Python: global scope and local scope. It affects how variables and functions are accessed and modified in different parts of the program. It also helps to prevent naming conflicts and improve the clarity and organization of the code.

Ques. What are lists and tuples in Python? What are their differences?

Ans. Lists and tuples are both data structures in Python that are used to store a collection of items. A list is a mutable data structure that can be modified after it is created. It is created using square brackets and items in a list are separated by commas. A tuple, on the other hand, is an immutable data structure that cannot be modified after it is created. It is created using parentheses and items in a tuple are separated by commas. 

A list in Python is a mutable sequence of elements, while a tuple is an immutable sequence of elements. This means that elements in a list can be changed, added, or removed, while elements in a tuple cannot be changed once they are defined.

Ques. What is PEP 8 in Python?

Ans. PEP 8 is a style guide for Python code that provides guidelines for formatting, naming conventions, and programming style. It is designed to make Python code more readable and consistent across different projects and developers.

Ques. Explain Python’s virtual environment.

Ans. A virtual environment in Python is a way to create an isolated environment for Python projects. It allows the users to install packages and dependencies for a specific project without affecting other projects on the same machine. This helps to ensure that dependencies and versions are consistent across different projects.

Ques. What are decorators in Python?

Ans. Decorators in Python are a way to modify the behaviour of a function or class without modifying its source code directly. They are defined using the ‘@’ symbol and can be used to add functionality such as logging, caching, or authentication to a function or class.

Ques. Name some areas where Python is applied.

Ans. Web and Internet development, games, scientific and computational applications, OS, GUI applications, language development, and business applications are some of the top areas where Python is used.

Ques. What are standard data types that are supported in Python?

Ans. Lists, numbers, strings, dictionaries and tuples are the standard data types that Python supports.

Ques. What is asyncio in Python?

Ans. Asyncio is a library in Python that allows developers to write asynchronous code. It has been available in Python since version 3.4, but it has become more popular in recent years due to the increasing demand for scalable and high-performance systems.

Top Python Interview Questions and Answers in 2023 - Intermediate

Some of the best and most asked Python interview questions along with their answers at the intermediate level are as follows - 

Ques. Explain the Lambda function used in Python.

Ans. A lambda function in Python is a small anonymous function that can take any number of arguments but can only have one expression. Lambda functions are often used as arguments to higher-order functions or as a way to write quick and simple functions without defining a formal function.

Ques. What is multithreading in Python?

Ans. Multithreading is a technique used in programming to achieve parallelism, where multiple threads of execution run concurrently within a single program. In Python, multithreading allows for the execution of multiple threads simultaneously within the same program, allowing for increased efficiency and responsiveness.

Multithreading in Python is achieved using the threading module, which provides a simple way to create and manage threads. Threads can be created by subclassing the Thread class or by using the Thread constructor to create a new thread object. Once a thread is created, it can be started using the start() method, which runs the target function in a separate thread. One of the main advantages of multithreading in Python is that it allows for the concurrent execution of multiple tasks, which can improve the performance and responsiveness of a program.

Ques. Define Map Function.

Ans. In Python, map() is a built-in function that applies a given function to each item of an iterable object and returns a new iterable object with the results. The syntax of the map() function is - map(function, iterable). 

The function parameter is the application that can be used for each item in the iterable object, while the iterable parameter is the object that contains the items to be processed. The map() function then returns a new iterable object that contains the results of applying the function to each item in the iterable.

Ques. What are the differences between NumPy and SciPy?

Ans. Some key differences between NumPy and SciPy are - 

• NumPy provides a basic set of tools for manipulating numerical arrays, while SciPy provides additional tools for solving scientific and engineering problems.
• NumPy provides fundamental array operations and basic linear algebra routines, while SciPy provides more advanced mathematical functions, such as optimization algorithms, interpolation, and signal processing.
• NumPy is mainly focused on numerical computing, while SciPy is focused on scientific computing, including numerical computing as well as more advanced scientific tasks.

Ques. What is Tkinter in Python?

Ans. Tkinter is a standard Python library used for creating GUIs. It provides a set of built-in GUI widgets that can be used to create desktop applications with a variety of user interfaces.

Tkinter is based on the Tk GUI toolkit, which was originally developed for the Tcl scripting language. It provides a simple and easy-to-use interface for building GUIs in Python and is included with most Python installations.

Ques. Explain Pickling and Unpickling.

Ans. Pickling and unpickling are operations in Python that allow you to serialize and deserialize objects. Serialization is the process of converting an object's state to a byte stream, while deserialization is the process of recreating the object from that byte stream.

Pickling converts an object hierarchy into a byte stream, while unpickling is the opposite process of creating an object hierarchy from a byte stream.

Ques. What are dataclasses?

Ans. Dataclasses are a new feature in Python that allows developers to define classes for storing data. They provide a simple and concise syntax for defining classes with default values and automatic generation of methods such as init, repr, and eq.

Ques. What is Jupyter Notebook in Python?

Ans. Jupyter Notebook is an interactive computing environment that allows developers to write code, visualize data, and share their results. It has become popular in recent years in data science and machine learning due to its ability to combine code, visualizations, and documentation in a single document.

Ques. What are the latest developments going on in Python in 2023?

Ans. Some of the latest developments in Python in 2023 include - 

• Performance improvements using PEP 659 and PEP 679.
• More type annotations.
• Better support for asynchronous programming.
• Improved machine learning support.
• Emphasis on inclusivity and sustainability.

Ques. When args and kwargs are used in Python?

Ans. When passing multiple arguments in a function, args is used. To pass multiple keyword arguments in a function, kwargs is used. 

Top Python Interview Questions and Answers in 2023 - Advanced

Some of the best and most asked Python interview questions along with their answers at the advanced level are as follows - 

Ques. What are namespaces? What is their use?

Ans. In Python, a namespace is a collection of names that are used to identify objects such as variables, functions, classes, and modules. Namespaces help to avoid naming conflicts by providing a way to uniquely identify objects within a program. Namespaces are useful because they allow users to organize their code and avoid naming conflicts. You can access variables, functions, and other objects within a namespace using dot notation. 

Namespaces are of the following types - 

• Local namespaces - contain names that are defined inside the function.
• Global namespaces - contain names that are defined at the module level.
• Built-in namespaces - contain names of built-in functions.

Namespaces are an important concept in Python programming that helps to organize and manage code and avoid naming conflicts.

Ques. What are the stages of a thread lifecycle in Python?

Ans. A thread lifecycle has the following stages - 

• Class creation to override thread class run method.
• Call to start the new thread. The thread is taken for scheduling.
• Thread execution starts and it goes to a running state.
• Thread waits for the call to a method with join () and sleep (). 
• Waiting thread is sent for scheduling.
• Running thread executes the terminates and reaches the dead state. 

Ques. What are help() and dir() functions?

Ans. The help() and dir() functions are built-in functions in Python that are used to obtain information about objects and their attributes.

The help() function is used to provide documentation on modules, classes, functions and methods. It displays a help message that describes how to use the object, including its parameters and return values. The dir() function is used to obtain a list of all attributes of an object. It returns a list of strings that contain the names of the attributes. 

Ques. What codes have to be used to get N maximum value indices in the Numpy array?

Ans. The following code can be applied to get N maximum value indices in the Numpy array- 

>>import numpy as np

>>arr=np.array([1, 3, 2, 4, 5])

>>print(arr.argsort( ) [ -N: ][: : -1]

Ques. Write a code to access a dataset which is uploaded on an online spreadsheet tool.

Ans. The following code can be used to access a dataset which is uploaded on an online spreadsheet tool-

>>link = “spreadsheet URL”

>>source = StringIO.StringIO(requests.get(link).content))

>>data = pd.read_csv(source)

Ques. What is PYTHONPATH?

Ans. PYTHONPATH is an environment variable in Python that specifies the search path for Python modules. When a module is imported in Python, the interpreter searches for the module in a set of directories, including the directory of the script that is running, the built-in modules, and the directories specified in the PYTHONPATH environment variable.

The PYTHONPATH variable is used to add custom directories to the search path, which allows importing modules from non-standard locations. For example, if a custom module is located in a directory that is not included in the default search path, a directory can be added to the PYTHONPATH environment variable to make the module accessible.

The PYTHONPATH environment variable is set as a list of directory paths separated by colons (on Unix-like systems) or semicolons (on Windows systems). 

Ques. What are .py and .pyc files?

Ans. In Python, .py files are source code files that contain Python code that can be executed by the Python interpreter. These files are written in plain text and are saved with the .py file extension. When a .py file is executed, the Python interpreter compiles the code into bytecode, which is a low-level representation of the code that can be executed more quickly. The bytecode is then saved in a .pyc file in the same directory as the source code file. The .pyc file has the same name as the .py file, but with a .pyc extension.

The next time the .py file is executed, the Python interpreter first checks if there is a corresponding .pyc file with the same name and in the same directory as the source code file. If a .pyc file exists, the interpreter loads the bytecode from the .pyc file instead of recompiling the source code.

The use of .pyc files improves the startup time of Python programs because the bytecode can be loaded more quickly than the source code can be compiled. Additionally, it can help to reduce the size of distribution packages by excluding the source code files and only including the .pyc files.

Ques. What are Flask and Django in Python?

Ans. Flask and Djando are both web frameworks for building web applications in Python.

Flask is a lightweight web framework that is designed to be simple and flexible. It provides a basic set of tools for building web applications but does not include many of the built-in features of other frameworks. It is often used for building small to medium-sized web applications, APIs and prototypes.

Django, on the other hand, is a more comprehensive web framework that includes a wide range of built-in features and tools for building web applications. It provides a full-stack solution for web development, including features like built-in ORM, user authentication and administrative tools. It is used for building large-scale web applications and content management systems. 

Ques. What is the split () function in Python? Write its syntax.

Ans. The split () function is a built-in method in Python which is used to separate a string into a list of substrings based on a specified separator. The basic syntax of split () function is - 

string.split(separator, maxsplit)

separator is the delimiter used to split the string, and maxsplit is an optional parameter that specifies the maximum number of splits to perform. If maxsplit is not provided, all occurrences of the separator are used to split the string.

Ques. How does Python manage memory?

Ans. Memory management in Python is managed automatically by the Python interpreter through a technique called "garbage collection". In Python, memory is allocated dynamically, meaning that the size of an object can change during runtime.

The Python interpreter uses a private heap to store all the Python objects that are created during program execution. The heap is managed by the interpreter's memory manager, which automatically allocates and deallocates blocks of memory for Python objects. When an object is no longer referenced by any part of the program, the memory manager marks the object as "garbage" and frees up the memory allocated to it.

Python also uses a reference counting system to keep track of how many references exist to a particular object. Whenever an object is assigned to a new variable, or passed as an argument to a function, its reference count is increased. When an object's reference count drops to zero, it means that the object is no longer being used and can be safely deleted. In addition to automatic garbage collection, Python also provides tools for manual memory management.

Conclusion

Python is a very strong and versatile programming language used in various industries. It is important to prepare well for a Python interview by reviewing common interview questions and problem-solving skills, irrespective of whether a candidate is a beginner or an experienced programmer. Candidates can better prepare themselves for a successful Python interview in 2023 and beyond, by understanding the concepts and techniques covered in this article in the form of questions and answers.