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Checking for allowed characters Regular Expression Regex in Python

Basics of Regular Expressions in Python, check the link below πŸ‘‡ πŸ‘‡
Regular Expressions Regex basic in Python πŸ‘ˆ πŸ‘ˆ

Also with table of contents about symbols and their usage in Regex

you can also use regex to split string. Scroll down for more!!!πŸ‘‡ πŸ‘‡

Python makes regular expressions available through the re module.

If you want to check that a string contains only a certain set of characters, in this case a-z, A-Z and 0-9, you can do so like this,

import re
def is_allowed(string):
characherRegex = re.compile(r'[^a-zA-Z0-9.]')
string =
return not bool(string)
print (is_allowed("abyzABYZ0099"))
# Output: 'True'

print (is_allowed("#*@#$%^"))
# Output: 'False'


You can also adapt the expression line from [^a-zA-Z0-9.] to [^a-z0-9.] , to disallow uppercase letters for


Executed using python3

Splitting a string using regular expressions

You can also use regular expressions to split a string. For example,

import re
data = re.split(r'\s+', 'James 94 Samantha 417 Scarlett 74')
print( data )

Output: [ ‘James’, ’94’, ‘Samantha’, ‘417’, ‘Scarlett’, ’74’ ]


Executed using python3

Replacing Strings using Regex Python
Replacements can be made on strings using re.sub. πŸ‘‡ πŸ‘‡ πŸ‘‡
Replacing Strings using Regular Expression Regex in
Replacing strings and Using group references Replacements with a small number of groups can be made.

The 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