Python interview questions | Python interview questions and answers

Python interview questions

Welcome to the Python Interview Questions section of sirfpadhai.in, In this section, we’ll go through various types of Python interview questions that can be used to gauge your proficiency with the language for the benefit of potential employers. Please send an email to hello@sirfpadhai.in if you have any queries regarding Python that are not answered here or elsewhere on our website.

What is Python?

Python is an object-oriented, high-level programming language, which is used in tasks such as website building, app development, machine learning, data analysis, web scraping, and natural language processing. Python is also called a general-purpose programming language. It started in the 1980s.

Due to the clear syntax and readability of Python language, it has become the most popular programming language in the world today. Python provides options like dynamic typing and dynamic binding. For this reason, it is used well in the field of rapid application development.

class HelloWorld{
  public static void main(String args[]{
    System.out.println("Hello World!!");
  }
}

• That’s a lot of code for such a simple function in Java.
• Now take a look at the same exercise written in Python code:

print("Hello World!!")

Explain how can you make a Python Script executable on Unix.

Script file must begin with #!/usr/bin/env python

What is PYTHONPATH in Python?

PYTHONPATH is a climate variable that you can set to add extra indexes where Python will search for modules and bundles. This is particularly valuable in keeping up with Python libraries that you don’t wish to introduce in the worldwide default area.

What are the key features of Python?

1. Easy to code
2. Easy to read
3. Expressive
4. Free and Open-Source
5. High-Level Language
6. Portable
7. Interpreted Language
8. Object-Oriented Language
9. Extensible
10. Embeddable
11. Large Standard Library
12. GUI Programming Support
13. Dynamically Typed

And many more…

What type of language is Python? Programming or scripting?

The difference between a scripting language and a programming language today is meaningless. It uses outmoded language. Between the two, there is really no distinction, and when you think about it, there never was. Perl and Python, which were once employed as scripting languages, are now entirely legitimate programming languages. Usually, they were translated. So disregard the scripting vs. non-scripting debate. It makes no sense.

What is Python good for?

Python is an interpreted language that is simple to learn since anyone with a working grasp of English can understand the commands that are used. Since libraries are growing and enabling one to accomplish more and more things, they may be utilized for almost any work. Python is the ideal language for learning everything, not just programming, thanks to these qualities. In the meanwhile, we’ll say the following:

1. Web and Internet Development
2. Desktop GUI
3. Scientific and Numeric Applications
4. Data Science
5. Software Development Applications
6. Applications in Education
7. Applications in Business
8. Database Access
9. Network Programming
10. Games, 3D Graphics

Is Python case-sensitive?

Yes. Like most widely used programming languages like Java, C, C++, etc, Python is also a case-sensitive language. This means, “Hello” and “hello” are not the same. In other words, it cares about the case- lowercase or uppercase.

What is PEP 8?

PEP 8 is a coding convention, a set of recommendations, about how to write your Python code more readable.

How Python is interpreted?

Python language is an interpreted language. Python program runs directly from the source code. It converts the source code that is written by the programmer into an intermediate language, which is again translated into machine language that has to be executed.

What is Scope in Python?

The scope of a variable is the area from which it is only accessible. Consider it to be the part of the code that allows the use of variables. Every Python object has a scope within which it operates. Here are a few instances of scope that Python code execution can create:

Local Scope: A variable defined inside a function is only used within that function and is part of the local scope of that function.

Global Variable: A global variable is one that is generated in the main body of the Python code and is a member of the global scope.

Module Scope: This term describes the program’s global items that are accessible from the present module.

What are Python decorators?

Python decorator is a specific change that we make in Python syntax to alter functions easily.

What built-in type does Python provide?

The most fundamental type that Python provides as a built-in is Object, anything that you care to name is a subclass of an object even an integer digit.

The principal built-in types are:

• numerics
• sequences
• mappings
• classes
• instances
• exceptions

There are mutable and Immutable types of Pythons built-in types.

Mutable built-in types

The methods that add, subtract, or rearrange their members in place, and don’t return a specific item, never return the collection instance itself but None.

1. List
2. Sets
3. Dictionaries

Immutable built-in types

1. Strings
2. Tuples
3. Numbers

What are the different types of operators in Python?

An operator is a symbol that represents an operation. The values ​​on which the operators operate are called operands. Operators are used to manipulate data and variables in the program. That is, operators are symbols that are used to perform mathematical or logical operations in the program.

There are two types of Python operators: – unary operators and binary operators.

The unary operator operates on only one operand. Whereas the binary operator operates on two operands.

For example- 4+6, where 4 and 6 are operands while + is an operator.

Python supports the following types of operators.

• Arithmetic Operators
• Comparison (Relational) Operators
• Assignment Operators
• Logical Operators
• Bitwise Operators
• Membership Operators
• Identity Operator

What is the purpose of **the operator?

The ** operator in Python exponentiates. x ** y stands for x raised to the power of y. The ** sign has a different meaning when used in function arguments and calling notations (passing and receiving arbitrary keyword arguments).

>>>2**4
16

What is lambda in Python?

Lambda functions are defined anonymously without any name. You assign them to an object and they are used by the same object name. This eliminates the need to write a complete function using multiple keywords.
In Python, normal functions are defined by the def keyword, and lambda functions are defined by the lambda keyword.

lambda <arguments> : expression

 
def key(x):
    return x[1]

a = [(1, 2), (3, 1), (5, 10), (11, -3)]
a.sort(key=key)

versus

 
a = [(1, 2), (3, 1), (5, 10), (11, -3)]
a.sort(key=lambda x: x[1])

How will you check in a string that all characters are digits?

Python isdigit() method checks if all the characters in the text are digits.

>>> "12345".isdigit()
True
>>> "a12345".isdigit()
False

Difference between del[], remove() and pop() on list?

• remove() : removes the first matching value, not a specific index.
• del[] : removes the item at a specific index.
• pop() : removes the item at a specific index and returns it.

remove()

>>> x = [1,2,3,4]
>>> x.remove(1)
>>> x
[2, 3, 4]

• remove() is the only one which searches the object

del[]

>>> x = [1,2,3,4]
>>> del x[2]
>>> x
[1, 2, 4]

• del[] allows the removal of a range of indexes because of list slicing.

pop()

>>> x = [1,2,3,4]
>>> x.pop(2)
3
>>> x
[1, 2, 4]

What are negative indices?

When an index is negative, you start counting from the right rather than the left. List[-1] denotes the last entry, list[-2] the next-to-last, and so forth.

>>> myList = [0, 1, 2, 3, 4, 5]
>>> print(myList[-1])
>>> 5
>>>
>>>print(myList[len(myList) -1] )
>>>5

As with positive indices, the last element is excluded from the slice when you perform a slice operation when using negative indices.

myList = [0,1,2,3,4,5]
print(myList[-3:-1])

Output:-

[3, 4]

How will you convert an object to a string in python?

Python str() is meant to produce a string representation of the object’s data .

 
myObject = 10
myStr = str(myObject)

Also, repr() is a similar method, which returns a printable representation of the given object.

var = 'foo'
print(repr(var))

How will you convert a string to an int in python?

The default built-in Python function called int() turns a string into an integer number. It accepts a string containing a number as an argument and returns the number as an integer in response:

>>> str = "1001"
>>> iStr = int(str)
>>>
>>> type(iStr)
<class 'int'>
>>>
>>> type(str)
<class 'str'>

What are membership operators?

There are two membership operators in Python: in operator and not in operator

• in operator – Evaluates to true if it finds a variable in the specified sequence and false otherwise.
  
• not in operator– Evaluates to true if it does not find a variable in the specified sequence and false otherwise.

What is the difference between a list and tuple?

What is a package in Python?

A collection of modules in Python is called a folder. Modules and subfolders can be found in packages.

Each package imported by an import statement creates a new namespace.

import module1, subfolder2, folder1,

OR

import names from folder1.subfolder2.module1

The __init .py file needs to be present in all of the directories and subfolders in order to import a package