[Python] camelCaseFilenames_to_underscore_filenames_(uncapitalized) - recursive, and renames itself ¯\_(ツ)_/¯

camelCase.py

import re
import glob
import os
import os.path

def camelCaseSplit(identifier):
	matches = [m.group(0) for m in re.finditer('.+?(?:(?<=[a-z])(?=[_A-Z])|(?<=[a-z])(?=[A-Z])|(?<=[A-Z])(?=[A-Z][a-z])|$)', identifier)]
	s = matches[0]
	for i in range(1, len(matches)):
		if matches[i][0] == "_":
			s += matches[i].lower()
		else:
			x = "_" + matches[i].lower()
			s += x
	print(s)
	return s

for f in glob.iglob(os.getcwd() + "/**/*", recursive=True):
	name, dummy  = os.path.splitext(f)
	os.rename(f, f.replace(name,  camelCaseSplit(name)))