str.isalnum
Check that the string is not empty and contains only letters and digits.
Python 3.13
str.isalnum()Return value
True or False; False for an empty string.
Examples
Letters and digits
Python 3.13
print('abc123'.isalnum())True
An underscore does not match, Cyrillic does
Python 3.13
print('user_1'.isalnum(), 'Привет2'.isalnum())False True
Details
Letters of any alphabet and digits match, while spaces, hyphens and underscores do not. To check a variable name, use str.isidentifier.