Extracting a number from a string using regular expressions

Question

I have the following string:

fname="VDSKBLAG00120C02 (10).gif"

How can I extract the value 10 from the string fname (using re)?

Answer 1

A simpler regex is \((\d+)\):

regex = re.compile(r'\((\d+)\)')
value = int(re.search(regex, fname).group(1))

Answer 2

regex = re.compile(r"(?<=\()\d+(?=\))")
value = int(re.search(regex, fname).group(0))

Explanation:

(?<=\() # Assert that the previous character is a (
\d+     # Match one or more digits
(?=\))  # Assert that the next character is a )