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Python Exercises

Python: Check that a string contains only a certain set of characters

Python Regular Expression: Exercise-1 with Solution

Write a Python program to check that a string contains only a certain set of characters (in this case a-z, A-Z and 0-9).

Sample Solution:-

Python Code:

import re
def is_allowed_specific_char(string):
    charRe = re.compile(r'[^a-zA-Z0-9.]')
    string = charRe.search(string)
    return not bool(string)

print(is_allowed_specific_char("ABCDEFabcdef123450")) 
print(is_allowed_specific_char("*&%@#!}{"))

Sample Output:

True                                                                                                          
False 

Flowchart:

Flowchart: Regular Expression - Check that a string contains only a certain set of characters.

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