I found an interesting problem on https://www.codewars.com/kata/57f8ff867a28db569e000c4a:
Modify the `kebabize` function so that it converts a camel case string into a kebab case.

Notes:
  - the returned string should only contain lowercase letters

I tried it in Python, but could not do it. Can you solve it?
import re

def kebabize(s):
    return re.sub('\B([A-Z])', r'-\1', re.sub('\d', '', s)).lower()