Python makes regular expressions available through the re module.
Special characters (like the character class brackets [ and ] below) are not matched literally:
import re match = re.search(r'[b]', 'a[b]c') print(match.group()) # Output: 'b'
By escaping the special characters, they can be matched literally:
import re match = re.search(r'\[b\]', 'a[b]c') print(match.group()) # Output: '[b]'
The re.escape() function can be used to do this for you:
import re
print(re.escape('a[b]c'))
# Output: 'a\\[b\\]c'
match = re.search(re.escape('a[b]c'), 'a[b]c')
print(match.group())
# Output: 'a[b]c'The re.escape() function escapes all special characters, so it is useful if you are composing a regular expression based on user input:
import re
username = 'A.C.' # suppose this came from the user
temp = re.findall(r'Hi {}!'.format(username), 'Hi A.C.! Hi ABCD!')
print(temp)
# Output: ['Hi A.C.!', 'Hi ABCD!']
temp = re.findall(r'Hi {}!'.format(re.escape(username)), 'Hi A.C.! Hi ABCD!')
print(temp)
# Output: ['Hi A.C.!']ILLUSTRATION USING PYTHON CLI
For the first part in using regular expressions and matching the string
you can visit this link –> 👇 👇
Matching the beginning of a string (Regex) Regular Expressions in python
The re.search() method takes a regular expression pattern and a string and searches for that pattern within the string. If the search is successful, search() returns a match object or None otherwise.
For the second part in using regular expression and searching the string
visit –> Searching – Regular Expressions (Regex) in Python
Replacing Strings using Regex Python
Replacements can be made on strings using re.sub. 👇 👇 👇
Replacing Strings using Regular Expression Regex in Python..-FcukTheCode.com
Replacing strings and Using group references Replacements with a small number of groups can be made.