Python regex removing non alpha numeric characters from string except brackets

Question

I have the following regex , which remove all no alpha numeric characters from a string text

re.sub(r'[^a-zA-Z0-9]',' ', text)

How can I modify this expression to include the characters '[' and ']' in the string text ?

Answer 1

Add [, ] to the charcter class ([ .. ]) with escaping.

re.sub(r'[^a-zA-Z0-9\[\]]',' ', text)

Example:

>>> re.sub(r'[^a-zA-Z0-9\[\]]', ' ', 'a,b[c-d]!')
'a b[c d] '