How to use re.IGNORECASE in re.finditer in REGEX?

for w in words:
   position = re.finditer(w, text, flags=re.IGNORECASE)

The above code attempts to find the word 'w' in a sentence 'text' irrespective of the case. But the output doesn't vary after using flags=re.IGNNORECASE. How can I use ignorecase specifically in finditer?