search

What is a regular expression in Python and how to use it?

A regular expression, often abbreviated as "regex" or "regexp", is a sequence of characters that define a search pattern. In Python, regular expressions can be used to search, match, and manipulate strings.

The **re** module in Python provides support for using regular expressions. To use regular expressions in Python, you need to import the **re** module and then use its functions to perform the necessary operations.

Here's an example of using regular expressions in Python to search for a pattern in a string:

import re

text = "The quick brown fox jumps over the lazy dog."
pattern = "fox"

match = re.search(pattern, text)

if match:
    print("Pattern found!")
else:
    print("Pattern not found.")
# Output: Pattern found!

In this example, the **re.search** function is used to search for the pattern **"fox"** in the string **text**. If a match is found, the **re.search** function returns a match object; otherwise, it returns **None**.

The **re** module provides various functions for working with regular expressions, including **re.match**, **re.findall**, and **re.sub**, among others. These functions can be used to match patterns, find all matches in a string, substitute matches with new strings, etc.

Related Questions You Might Be Interested