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Python and Interview Questions

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50 Top Python Interview Questions and Answers

Posted in Python, Interview Questions
Python Interview Questions

Table of Contents

Irrespective of the source you pick a list of best programming languages to learn in 2022 from, one name that will always find its place there is Python.

So, the answer is yes, if you are asking whether a lucrative career is possible by dedicating yourself to the interpreted, high-level, general-purpose programming language i.e. learning Python.

Let's get started with top interview questions on Python.

Top Python Interview Questions and Answers

Once you’ve had enough understanding of the various concepts of Python, it’s time to give a shot at some interviews. To increase your chances of clearing them, here is a list of top Python interview questions that you must know answers to:

Basic Level Python Interview Questions for Freshers and Beginners

Question: Explain Python?

Answer: Python is a highly comprehensive, interactive, and object-oriented scriptwriting language. It is specifically developed with the purpose of making the content highly readable among the net surfers. Python makes use of various English keywords other than just punctuations. It also has lesser syntactical constructions like in other languages.

Question: What are the distinct features of Python?

Answer: The distinct features of Python include the following.

  1. Structured and functional programmings are supported.
  2. It can be compiled to byte-code for creating larger applications.
  3. Develops high-level dynamic data types.
  4. Supports checking of dynamic data types.
  5. Applies automated garbage collection.
  6. It could be used effectively along with Java, COBRA, C, C++, ActiveX, and COM.

Question: What is Pythonpath?

Answer: A Pythonpath tells the Python interpreter to locate the module files that can be imported into the program. It includes the Python source library directory and source code directory.

Question: Can we preset Pythonpath?

Answer: Yes, we can preset Pythonpath as a Python installer.

Question: Why do we use Pythonstartup environment variable?

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

Question: What is the Pythoncaseok environment variable?

Answer: Pythoncaseok environment variable is applied in Windows with the purpose to direct Python to find the first case insensitive match in an import statement.

Question: What are the supported standard data types in Python?

Answer: The supported standard data types in Python include the following.

  1. List.
  2. Number.
  3. String.
  4. Dictionary.
  5. Tuples.

Question: Define tuples in Python?

Answer: Tuples is a sequence data type in Python. The number of values in tuples are separated by commas.

Question: What is the major difference between tuples and lists in Python?

Answer: There are several major differences between tuples and lists in Python, which include the following:



Tuples are similar to a list, but they are enclosed within parenthesis, unlike the list.

The list is used to create a sequence.

The element and size can be changed.

The element and size cannot be changed.

They cannot be updated.

They can be updated.

They act as read-only lists.

They act as a changeable list.

Tuples are surrounded by ( )

Lists are surrounded by [ ]

Example of Tuple Code is, tup = (1, "a", "string", 1+2)

Example of Lists Code is, L = [1, "a" , "string" , 1+2]

Get Certified And Get Hired!


Question: What are the positive and negative indices?

Answer:  In the positive indices are applied the search beings from left to the right. In the case of the negative indices, the search begins from right to left. For example, in the array list of size n the positive index, the first index is 0, then comes 1 and until the last index is n-1. However, in the negative index, the first index is -n, then -(n-1) until the last index will be -1.

Question: What can be the length of the identifier in Python?

Answer: The length of the identifier in Python can be of any length. The longest identifier will violate from PEP – 8 and PEP – 20.

Question: Define Pass statement in Python?

Answer: 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.

Question: What are the limitations of Python?

Answer: There are certain limitations of Python, which include the following:

  1. It has design restrictions.
  2. It is slower when compared with C and C++ or Java.
  3. It is inefficient in mobile computing.
  4. It consists of an underdeveloped database access layer.

Question: Do runtime errors exist in Python? Give an example?

Answer: Yes, runtime errors exist in Python. For example, if you are duck typing and things look like a duck, then it is considered as a duck even if that is just a flag or stamp or any other thing. The code, in this case, would be A Run-time error. For example, Print “Hackr io”, then the runtime error would be the missing parenthesis that is required by print ( ).

Question: Can we reverse a list in Python?

Answer: Yes, we can reserve a list in Python using the reverse() method. The code can be depicted as follows.

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

Question: Why do we need a break in Python?

Answer: Break helps in controlling the Python loop by breaking the current loop from execution and transfer the control to the next block.

Question: Why do we need a continue in Python?

Answer: A continue also helps in controlling the Python loop but by making jumps to the next iteration of the loop without exhausting it.

Question: Can we use a break and continue together in Python? How?

Answer:  Break and continue can be used together in Python. The break will stop the current loop from execution, while jump will take to another loop.

Question: Does Python support an intrinsic do-while loop?

Answer: No Python does not support an intrinsic do-while loop.

Question: How many ways can be applied for applying reverse string?

Answer: There are five ways in which the reverse string can be applied which include the following.

  1. Loop
  2. Recursion
  3. Stack
  4. Extended Slice Syntax
  5. Reversed

Question: What are the different stages of the Life Cycle of a Thread?

Answer: The different stages of the Life Cycle of a Thread can be stated as follows.

  • Stage 1: Creating a class where we can override the run method of the 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 wherein the thread starts execution, and it reaches the running state.
  • Stage 4: Thread wait until the calls to methods including join() and sleep() takes place. 
  • Stage 5: After the waiting or execution of the thread, the waiting thread is sent for scheduling.
  • Stage 6: Running thread is done by executing the terminates and reaches the dead state.

Question: What is the purpose of relational operators in Python?

Answer: The purpose of relational operators in Python is to compare values.

Question: What are assignment operators in Python?

Answer: The assignment operators in Python can help in combining all the arithmetic operators with the assignment symbol.

Question: Why do we need membership operators in Python?

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

Question: How are identity operators different than the membership operators?

Answer: Unlike membership operators, the identity operators compare the values to find out if they have the same value or not.

Question: Describe how multithreading is achieved in Python.

Answer: Even though Python comes with a multi-threading package, if the motive behind multithreading is to speed the code then using the package is not the go-to option.

The package has something called the GIL or Global Interpreter Lock, which is a construct. It ensures that one and only one of the threads execute at any given time. A thread acquires the GIL and then do some work before passing it to the next thread.

This happens so fast that to a user it seems that threads are executing in parallel. Obviously, this is not the case as they are just taking turns while using the same CPU core. Moreover, GIL passing adds to the overall overhead to the execution.

Hence, if you intend to use the threading package for speeding up the execution, using the package is not recommended.

Question: Draw a comparison between the range and xrange in Python.

Answer: In terms of functionality, both range and xrange are identical. Both allow for generating a list of integers. The main difference between the two is that while range returns a Python list object, xrange returns an xrange object.

Xrange is not able to generate a static list at runtime the way range does. On the contrary, it creates values along with the requirements via a special technique called yielding. It is used with a type of object known as generators.

If you have a very enormous range for which you need to generate a list, then xrange is the function to opt for. This is especially relevant for scenarios dealing with a memory-sensitive system, such as a smartphone.

The range is a memory beast. Using it requires much more memory, especially if the requirement is gigantic. Hence, in creating an array of integers to suit the needs, it can result in a Memory Error and ultimately lead to crashing the program.

Question: Explain Inheritance and its various types in Python?

Answer: Inheritance enables a class to acquire all the members of another class. These members can be attributes, methods, or both. By providing reusability, inheritance makes it easier to create as well as maintain an application.

The class which acquires is known as the child class or the derived class. The one that it acquires from is known as the superclass or base class or the parent class. There are 4 forms of inheritance supported by Python:

  • Single Inheritance – A single derived class acquires from on single superclass.
  • Multi-Level Inheritance – At least 2 different derived classes acquire from two distinct base classes.
  • Hierarchical Inheritance – A number of child classes acquire from one superclass
  • Multiple Inheritance – A derived class acquires from several superclasses.

Question: Explain how is it possible to Get the Google cache age of any URL or webpage using Python.

Answer: In order to Get the Google cache age of any URL or webpage using Python, the following URL format is used:


Simply replace URLGOESHERE with the web address of the website or webpage whose cache you need to retrieve and see in Python.

Question: Give a detailed explanation about setting up the database in Django.

Answer: The process of setting up a database is initiated by using the command edit mysite/setting.py. This is a normal Python module with a module-level representation of Django settings. Django relies on SQLite by default, which is easy to be used as it doesn’t require any other installation.

SQLite stores data as a single file in the filesystem. Now, you need to tell Django how to use the database. For this, the project’s setting.py file needs to be used. Following code must be added to the file for making the database workable with the Django project:

 'default': {
 'ENGINE' : 'django.db.backends.sqlite3',
 'NAME' : os.path.join(BASE_DIR, 'db.sqlite3'),

If you need to use a database server other than the SQLite, such as MS SQL, MySQL, and PostgreSQL, then you need to use the database’s administration tools to create a brand new database for your Django project.

You have to modify the following keys in the DATABASE ‘default’ item to make the new database work with the Django project:

  • ENGINE – For example, when working with a MySQL database replace ‘django.db.backends.sqlite3’ with ‘django.db.backends.mysql’
  • NAME – Whether using SQLite or some other database management system, the database is typically a file on the system. The NAME should contain the full path to the file, including the name of that particular file.

NOTE: - Settings like Host, Password, and User needs to be added when not choosing SQLite as the database.

Check out the advantages and disadvantages of Django.


Advanced Level Python Interview Questions for Experienced and Professionals

Question: How will you differentiate between deep copy and shallow copy?

Answer: We use a shallow copy when a new instance type gets created. It keeps the values that are copied in the new instance. Just like it copies the values, the shallow copy also copies the reference pointers.

Reference points copied in the shallow copy reference to the original objects. Any changes made in any member of the class affect the original copy of the same. Shallow copy enables faster execution of the program.

Deep copy is used for storing values that are already copied. Unlike shallow copy, it doesn’t copy the reference pointers to the objects. Deep copy makes the reference to an object in addition to storing the new object that is pointed by some other object.

Changes made to the original copy will not affect any other copy that makes use of the referenced or stored object. Contrary to the shallow copy, deep copy makes execution of a program slower. This is due to the fact that it makes some copies for each object that is called.

Question: How will you distinguish between NumPy and SciPy?

Answer: Typically, NumPy contains nothing but the array data type and the most basic operations, such as basic element-wise functions, indexing, reshaping, and sorting. All the numerical code resides in SciPy.

As one of NumPy’s most important goals is compatibility, the library tries to retain all features supported by either of its predecessors. Hence, NumPy contains a few linear algebra functions despite the fact that these more appropriately belong to the SciPy library.

SciPy contains fully-featured versions of the linear algebra modules available to NumPy in addition to several other numerical algorithms.

Question: Observe the following code:

A0 = dict(zip(('a','b','c','d','e'),(1,2,3,4,5)))
A1 = range(10)A2 = sorted([i for i in A1 if i in A0])
A3 = sorted([A0[s] for s in A0])
A4 = [i for i in A1 if i in A3]
A5 = 
A6 = [[i,i*i] for i in A1]

Write down the output of the code.


A0 = {'a': 1, 'c': 3, 'b': 2, 'e': 5, 'd': 4} # the order may vary
A1 = range(0, 10)
A2 = []
A3 = [1, 2, 3, 4, 5]
A4 = [1, 2, 3, 4, 5]
A5 =
A6 = [[0, 0], [1, 1], [2, 4], [3, 9], [4, 16], [5, 25], [6, 36], [7, 49], [8, 64], [9, 81]]

Question: Python has something called the dictionary. Explain using an example.

Answer: A dictionary in Python programming language is an unordered collection of data values such as a map. Dictionary holds key:value pair. It helps in defining a one-to-one relationship between keys and values. Indexed by keys, a typical dictionary contains a pair of keys and corresponding values.

Let us take an example with three keys, namely Website, Language, and Offering. Their corresponding values are hackr.io, Python, and Tutorials. The code for the example will be:

print dict[Website] #Prints hackr.io
print dict[Language] #Prints Python
print dict[Offering] #Prints Tutorials

Question: Python supports negative indexes. What are they and why are they used?

Answer: The sequences in Python are indexed. It consists of positive and negative numbers. Positive numbers use 0 as the first index, 1 as the second index, and so on. Hence, any index for a positive number n is n-1.

Unlike positive numbers, index numbering for the negative numbers start from -1 and it represents the last index in the sequence. Likewise, -2 represents the penultimate index. These are known as negative indexes. Negative indexes are used for:

  • Removing any new-line spaces from the string, thus allowing the string to except the last character, represented as S[:-1]
  • Showing the index to representing the string in the correct order

Question: Suppose you need to collect and print data from IMDb top 250 Movies page. Write a program in Python for doing so. (NOTE: - You can limit the displayed information for 3 fields; namely movie name, release year, and rating.)


from bs4 import BeautifulSoup
import requests
import sys
url = 'http://www.imdb.com/chart/top'
response = requests.get(url)
soup = BeautifulSoup(response.text)
tr = soup.findChildren("tr")
tr = iter(tr)
for movie in tr:
title = movie.find('td', {'class': 'titleColumn'} ).find('a').contents[0]
year = movie.find('td', {'class': 'titleColumn'} ).find('span', {'class': 'secondaryInfo'}).contents[0]
rating = movie.find('td', {'class': 'ratingColumn imdbRating'} ).find('strong').contents[0]
row = title + ' - ' + year + ' ' + ' ' + rating 

Question: Take a look at the following code:

try: if '1' != 1: 
raise "someError"
else: print("someError has not occured")
except "someError": pr
int ("someError has occured")

What will be the output?

Answer: The output of the program will be “invalid code.” This is because a new exception class must inherit from a BaseException.

Question: What do you understand by monkey patching in Python?

Answer: The dynamic modifications made to a class or module at runtime are termed as monkey patching in Python. Consider the following code snippet:

# m.py
class MyClass:
def f(self):
print "f()"

We can monkey-patch the program something like this:

import m
def monkey_f(self):
print "monkey_f()"
m.MyClass.f = monkey_f
obj = m.MyClass()

The output for the program will be monkey_f().

The examples demonstrate changes made in the behavior of f() in MyClass using the function we defined i.e. monkey_f() outside of the module m.

Question: What do you understand by the process of compilation and linking in Python?

Answer: In order to compile new extensions without any error, compiling and linking is used in Python. Linking initiates only and only when the compilation is complete.

In the case of dynamic loading, the process of compilation and linking depends on the style that is provided with the concerned system. In order to provide dynamic loading of the configuration setup files and rebuilding the interpreter, the Python interpreter is used.

Question: What is Flask and what are the benefits of using it?

Answer: Flask is a web microframework for Python with Jinja2 and Werkzeug as its dependencies. As such, it has some notable advantages:

  • Flask has little to no dependencies on external libraries
  • Because there is a little external dependency to update and fewer security bugs, the web microframework is lightweight to use.
  • Features an inbuilt development server and a fast debugger.

Question: What is the map() function used for in Python?

Answer: The map() function applies a given function to each item of an iterable. It then returns a list of the results. The value returned from the map() function can then be passed on to functions to the likes of the list() and set().

Typically, the given function is the first argument and the iterable is available as the second argument to a map() function. Several tables are given if the function takes in more than one arguments.

Question: What is Pickling and Unpickling in Python?

Answer: The Pickle module in Python allows accepting any object and then converting it into a string representation. It then dumps the same into a file by means of the dump function. This process is known as pickling.

The reverse process of pickling is known as unpickling i.e. retrieving original Python objects from a stored string representation.

Question: Whenever Python exits, all the memory isn’t deallocated. Why is it so?

Answer: Upon exiting, Python’s built-in effective cleanup mechanism comes into play and try to deallocate or destroy every other object.

However, Python modules that are having circular references to other objects or the objects that are referenced from the global namespaces aren’t always deallocated or destroyed.

This is because it is not possible to deallocate those portions of the memory that are reserved by the C library.

Question: Write a program in Python for getting indices of N maximum values in a NumPy array.


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

Question: Write code to show randomizing the items of a list in place in Python along with the output.


from random import shuffle
x = ['hackr.io', 'Is', 'The', 'Best', 'For', 'Learning', 'Python']
['For', 'Python', 'Learning', 'Is', 'Best', 'The', 'hackr.io']

Question: Explain memory managed in Python?

Answer: Python private heap space takes place of memory management in Python. It contains all Python objects and data structures. The interpreter is responsible to take care of this private heap and the programmer does not have access to it. The Python memory manager is responsible for the allocation of Python heap space for Python objects. The programmer may access some tools for the code with the help of the core API. Python also provides an inbuilt garbage collector, which recycles all the unused memory and frees the memory and makes it available to heap space.

Question: What is the lambda function?

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

a = lambda x,y : x+y
print(a(5, 6))

Question: What are Python decorators?

Answer: A specific change made in Python syntax to alter the functions easily are termed as Python decorators.

Question: Differentiate between list and tuple.

Answer: Tuple is not mutable it can be hashed eg. key for dictionaries. On the other hand, lists are mutable.

Question: How are arguments passed in Python? By value or by reference?

Answer: All of the Python is an object and all variables hold references to the object. The reference values are according to the functions; as a result, the value of the reference cannot be changed.

Question: What are the built-in types provided by the Python?


Mutable built-in types:

  • Lists
  • Sets
  • Dictionaries

Immutable built-in types:

  • Strings
  • Tuples
  • Numbers

Question: How a file is deleted in Python?

Answer: The file can be deleted by either of these commands:


Question: What are Python modules?

Answer: 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 built-in modules some of which are:

  • os
  • sys
  • math
  • random
  • data time
  • JSON

Question: What is the // operator? What is its use?

Answer: The // is a Floor Divisionoperator used for dividing two operands with the result as quotient displaying digits before the decimal point. For instance, 10//5 = 2 and 10.0//5.0 = 2.0.

Question: What is the split function used for?

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

Question: Explain the Dogpile effect.

Answer: The event when the cache expires and websites are hit by multiple requests made by the client at the same time. Using a semaphore lock prevents the Dogpile effect. In this system when value expires, the first process acquires the lock and starts generating new value.

Question: What is a pass in Python?

Answer: No-operation Python statement refers to pass. It is a place holder in the compound statement, where there should have a blank left or nothing written there.

Question: Is Python a case sensitive language?

Answer: Yes Python is a case sensitive language.

Question: Define slicing in Python.

Answer: Slicing refers to the mechanism to select the range of items from sequence types like lists, tuples, strings.

Question: What are docstring?

Answer: Docstring is a Python documentation string, it is a way of documenting Python functions, classes and modules.

Question: What is [::-1} used for?

Answer: [::-1} reverses the order of an array or a sequence. However, the original array or the list remains unchanged.

import array as arr

Question: Define Python Iterators.

Answer: Group of elements, containers or objects that can be traversed.

Question: How are comments written in Python?

Answer: Comments in Python start with a # character, they can also be written within docstring(String within triple quotes)

Question: How to capitalize the first letter of string?

Answer: Capitalize() method capitalizes the first letter of the string, and if the letter is already capital it returns the original string

Question: What is, not and in operators?

Answer: Operators are functions that take two or more values and returns the corresponding result.

  • is: returns true when two operands are true
  • not: returns inverse of a boolean value
  • in: checks if some element is present in some sequence.

Question: How are files deleted in Python?

Answer: To delete a file in Python:

  1. Import OS module
  2. Use os.remove() function

Question: How are modules imported in Python?

Answer: Modules are imported using the import keyword by either of the following three ways:

import array 
import array as arr
from array import *

Question: What is monkey patching?

Answer: Dynamic modifications of a class or module at run-time refers to a monkey patch.

Question: Does Python supports multiple inheritances?

Answer: Yes, in Python a class can be derived from more than one parent class.

Question: What does the method object() do?

Answer: The method returns a featureless object that is base for all classes. This method does not take any parameters.

Question: What is pep 8?

Answer: Python Enhancement Proposal or pep 8 is a set of rules that specify how to format Python code for maximum readability.

Question: What is namespace in Python?

Answer: A naming system used to make sure that names are unique to avoid naming conflicts refers to as Namespace.

Question: Is indentation necessary in Python?

Answer: Indentation is required in Python if not done properly the code is not executed properly and might throw errors. Indentation is usually done using four space characters.

Question: Define a function in Python

Answer: A block of code that is executed when it is called is defined as a function. Keyword def is used to define a Python function.

Question: Define self in Python

Answer: An instance of a class or an object is self in Python. It is included as the first parameter. It helps to differentiate between the methods and attributes of a class with local variables.


So, that sums up the list of best Python interview questions. Learning never gets easier, you need to get better. So, here are some top choices for Python books to double-check your Python preparation.

As a high-in-demand language used by Data Science candidates, learning Python is always a plus. So here is a suitable course to enhance your skills in Python: Python for Data Structures, Algorithms, and Interviews.

You can also have this comprehensive Python book for your interview reference. It helps you prepare the better way for upcoming interviews: Elements of Programming Interviews in Python: The Insiders' Guide.

All the best for your interview!

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Vijay Singh

Vijay Singh

My name is Vijay Singh Khatri, and I enjoy meeting new people and finding ways to help them have an uplifting experience. I have had a variety of customer service opportunities, through which I was able to have fewer returned products and increased repeat customers, when compared with co-workers. Currently working with hackr.io View all posts by the Author

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Mahaboob subhani
Mahaboob subhani

I want interview questions for freshers


The answer for "What is the major difference between tuples and lists in Python?" needs correction. In second difference both answers must be interchanges.

Teri White
Teri White

What is main() in Python?

Abraham Rodgers
Abraham Rodgers

It is the point of execution for any program. It’s very important because no program runs as a module and they run when they are executed.

Cary Quinn
Cary Quinn

What is __ init __ in Python?

Katie Walsh
Katie Walsh

It’s an automatically called Python method on the allocation of memory for any new object. The purpose of __init__ is to initialize the qualities of the new object.

Kay Hansen
Kay Hansen

Is C++ or Python better?

Jan Gilbert
Jan Gilbert

It is not easy to decide which one is better from both C++ and Python, as both the languages are for general purposes. But talking about the complications, Python is better as Python is easy to read as well as understand because of its high level. On the other hand, C++ has its roots immersed in C and is more complicated for beginners. Python is better for beginners.

Kristina Lawrence
Kristina Lawrence

What does %s mean in Python?

Connie Moreno
Connie Moreno

% is called ‘Modulus’ in Python. It is a kind of arithmetic operation. Modulus is used to return the remainders when one operand is divided with another operand.

Clara Williamson
Clara Williamson

What is the use of * in Python?

Domingo Walton
Domingo Walton

Asterisk/star or * operation has different uses in Python, and all these are used at different times. Some of its main uses are:
as a multiplication symbol for numerics and data, and
it’s also used to denote repetition in certain lists or tuples.

Kourtney Omalley
Kourtney Omalley

What are the built in modules in Python?

Howard Wilson
Howard Wilson

There are several hundreds of built-in modules in Python. Unlike other modules, they are automatically loaded as soon as the interpreter starts. asynchat, IPython, selectors, shlex, and warnings are some of the various inbuilt Python modules. You can use the following command in Python console to get a list of all available inbuilt Python modules:
>>> help(‘modules’)

Libby Blue
Libby Blue

What is Python API?

Clove Duke
Clove Duke

An API (Application Programming Interface) is a collection of programming instructions and standards for accessing web-based software applications. A Python API is a type of plan that you can use for building Python-based applications. There are several Python APIs available to choose from

Siobhan Briones
Siobhan Briones

What is difference between framework and library?

Sebastian Matthias
Sebastian Matthias

Although conceptually, there is no difference between a Python package and Python library, we can still differentiate the two. A Python package is a collection of various Python modules, where each module is a collection of some functions and global variables. The library is a collection of various Python packages

Benny Swordsmith
Benny Swordsmith

A Python library is a set of classes or functions, also termed as modules, which have certain functionalities. A Python framework is simply a collection of several Python libraries that directs the code flow of a Python program


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