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Python Regular Expressions in Python Introduction to Regular Expressions Word Length

object of type 'NoneType' has no len()

What does this mean? I couldn't figure out where's wrong with my code.

word_length.py
import re

# EXAMPLE:
# >>> find_words(4, "dog, cat, baby, balloon, me")
# ['baby', 'balloon']

def find_words(count, string):
    re.findall(r'\w{count,}', string)

1 Answer

Steven Parker
Steven Parker
215,958 Points

I don't understand the error message either, but I'd bet you didn't really want the word "count" in your regex string.

You probably want to use concatenation or "format" to put the value of the argument named "count" into the regex instead.