Tutorial Playlist

Python Tutorial for Beginners


The Best Tips for Learning Python

Lesson - 1

How to Install Python on Windows?

Lesson - 2

Top 10 Python IDEs in 2022: Choosing The Best One

Lesson - 3

A Beginner’s Guide To Python Variables

Lesson - 4

Understanding Python If-Else Statement

Lesson - 5

Python Numbers: Integers, Floats, Complex Numbers

Lesson - 6

Python Strings | Simplilearn Python Tutorial

Lesson - 7

The Basics of Python Loops

Lesson - 8

Python For Loops Explained With Examples

Lesson - 9

Introduction to Python While Loop

Lesson - 10

Everything You Need to Know About Python Arrays

Lesson - 11

All You Need To Know About Python List

Lesson - 12

How to Easily Implement Python Sets and Dictionaries

Lesson - 13

A Handy Guide to Python Tuples

Lesson - 14

Everything You Need to Know About Python Slicing

Lesson - 15

Python Regular Expression (RegEX)

Lesson - 16

Learn A to Z About Python Functions

Lesson - 17

Objects and Classes in Python: Create, Modify and Delete

Lesson - 18

Python OOPs Concept: Here's What You Need to Know

Lesson - 19

An Introduction to Python Threading

Lesson - 20

Getting Started With Jupyter Network

Lesson - 21

PyCharm Tutorial: Getting Started with PyCharm

Lesson - 22

The Best NumPy Tutorial for Beginners

Lesson - 23

The Best Python Pandas Tutorial

Lesson - 24

An Introduction to Matplotlib for Beginners

Lesson - 25

The Best Guide to Time Series Analysis In Python

Lesson - 26

An Introduction to Scikit-Learn: Machine Learning in Python

Lesson - 27

A Beginner's Guide To Web Scraping With Python

Lesson - 28

Python Django Tutorial: The Best Guide on Django Framework

Lesson - 29

Top 10 Reason Why You Should Learn Python

Lesson - 30

10 Cool Python Project Ideas For Beginners in 2021

Lesson - 31

The Best Ideas for Python Automation Projects

Lesson - 32

12 Tips On How To Become a Python Developer

Lesson - 33

The Best Guide for RPA Using Python

Lesson - 34

Comprehending Web Development With PHP vs. Python

Lesson - 35

The Best Tips for Learning Python - REMOVE

Lesson - 36

The Best Way to Learn About Box and Whisker Plot

Lesson - 37

An Interesting Guide to Visualizing Data Using Python Seaborn

Lesson - 38

The Complete Guide to Data Visualization in Python

Lesson - 39

Everything You Need to Know About Game Designing With Pygame in Python

Lesson - 40

The Complete Simplified Guide to Python Bokeh

Lesson - 41

Top 150 Python Interview Questions and Answers for 2022

Lesson - 42

The Supreme Guide to Understand the Workings of CPython

Lesson - 43
Python Regular Expression (RegEX)

One of today’s most popular programming languages, Python has many powerful features that enable data scientists and analysts to extract real value from data. One of those, regular expressions in Python, are special collections of characters used to describe or search for patterns in a given string. They are mainly used for data cleaning or pattern matching in text files.  

What is Python Regular Expression (RegEx)?

A Python regular expression is a sequence of metacharacters that define a search pattern. We use these patterns in a string-searching algorithm to "find" or "find and replace" on strings. 

The term "regular expressions" is frequently shortened to "RegEx".

In this guide, we will learn the basics of regular expressions in Python through a demonstration We will begin by importing our “re” module. 


Fig: Importing regular expression module (re)

RegEx Functions

The “re” module provides a set of functions that enables us to search a string for a match. Some of the functions are listed below:

  • findall() function

The findall() function returns a list containing all matches.



Fig: findall() function

  • search() function  

The search() function takes a regular expression pattern and a string, and it searches for that pattern within the string. If the search is successful, search() returns a match object. Otherwise, it doesn’t return any.



Fig: search() function

  • split() function

The split() function returns a list that shows where the string has been split at each match.


Fig: split() function

It splits the string when it encounters space in a string.

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Python RegEx: Metacharacters

Every character in a Python RegEx is either a metacharacter or a regular character. A metacharacter has a special meaning, whereas a regular character matches itself.

Some of the basic metacharacters used in RegEx include:

  • “^” 

The ‘ ^ ’ character checks if the string starts with a particular word or character.



Fig:  ^ character in Python RegEx

  • “$”

The ‘$‘ character checks if the string ends with a particular word or character.


  • “|”

The ‘ | ‘ character is used to check either/or condition.


Fig: | character

  • “+”

This matches one or more occurrences of a character in a string.



Fig: + character

  • “*”

This returns the zero or more occurrences of a character in a string.



Fig: * character



{ }

Matches exactly the specified number of occurrences


Matches zero or more occurrences


Matches one or more occurrences

[ ] 

Matches a set of characters

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Python RegEx - Special sequences

A special sequence is a ‘ \ ‘ symbol, followed by one of the particular characters.  Some special sequences include:

  • \A

This checks if the string starts with a particular character.



Fig: \A sequence in Python RegEx

  • “\s”

The \s sequence returns a match when the string contains white space characters.



Fig: \s sequence

  • “\d”

The \d sequence checks if there are any digits in the given string.



Fig: \d sequence

  • “\Z”

The \Z sequence checks if the string ends with a particular word.


Fig: \Z sequence

  • “\w”

The \w sequence returns a match at every word character.



Fig: \w sequence in Python RegEx

Python RegEx - Sets



[ agh ]

Returns a match when any of the mentioned characters is present

[ a-h ]

Returns a match for lower case characters between a and h

[ ^agh ]

Returns a match for every character except a,g,and h

  • “[agh]”



Fig: Sets example

  • “[a-h]”


Fig: Sets example in Python RegEx

  • “[^agh]”



Fig: Sets example

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In this article, we discussed Python regular expressions. We looked at various functions and metacharacters in Python RegEx through demonstrations. 

If you have any questions, please ask them in the comments section, and we'll have our experts answer them for you promptly.

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About the Author

Aryan GuptaAryan Gupta

Aryan is a tech enthusiast who likes to stay updated about trending technologies of today. He is passionate about all things technology, a keen researcher, and writes to inspire. Aside from technology, he is an active football player and a keen enthusiast of the game.

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