Python | How to work with special characters in python

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Special characters

In the "re" module, special characters are used to match certain patterns of text. Here are a few examples:

.: Matches any single character except a newline.
^: Matches the beginning of a string or line.
$: Matches the end of a string or line.
\s: Matches any whitespace character (including spaces, tabs, and newlines).
\S: Matches any non-whitespace character.
\d: Matches any digit character (0-9).
\D: Matches any non-digit character.
\w: Matches any word character (letters, digits, or underscores).
\W: Matches any non-word character.

Here's an example of using special characters in the "re" module in Python:

import re

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

pattern1 = "b..." # Match any three characters starting with "b"

pattern2 = "^The" # Match "The" at the beginning of the string

pattern3 = "dog.$" # Match "dog" at the end of the string

pattern4 = "\s" # Match any whitespace character

pattern5 = "\d" # Match any digit character

pattern6 = "\w+" # Match one or more word characters

# Use the findall() function to find all matches of the pattern in the text

matches1 = re.findall(pattern1, text)

matches2 = re.findall(pattern2, text)

matches3 = re.findall(pattern3, text)

matches4 = re.findall(pattern4, text)

matches5 = re.findall(pattern5, text)

matches6 = re.findall(pattern6, text)

print("Matches for pattern1:", matches1)

print("Matches for pattern2:", matches2)

print("Matches for pattern3:", matches3)

print("Matches for pattern4:", matches4)

print("Matches for pattern5:", matches5)

print("Matches for pattern6:", matches6)

In this example, we are using different special characters to match certain patterns in the given text. We are using the findall() function to find all occurrences of the pattern in the text, and then printing out the matches for each pattern.

Note that you can use these special characters in combination with other regular expression syntax, such as quantifiers and grouping with parentheses, to create more complex patterns.