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Python Regular Expressions in Python Introduction to Regular Expressions Word Length

How to find words with x number of characters using a variable?

So, I passed this challenge, cheating the code, because I know the count number entered is 6, so I coded re.findall(f'\w{6,}', string), however, I'm not getting how is this supposed to be solved.

If I use the variable count as an integer which would provide the number of word characters findall should find, I get that the syntax is wrong, so what's the solution?

import re

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

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

1 Answer

Chris Freeman
Chris Freeman
Treehouse Moderator 68,063 Points

Hey Gustavo Guzmán, there are many ways to get this done. The main point being getting count interpreted as a variable and not the five characters “count”

  • build the regex in pieces: r'\w{‘ + str(count) + ‘,}'

When using format or f-strings, the field count delimiters {} get mistaken for format fields so curly brackets you wish to not be used for formatting need to doubled. This can lead to triple brackets (doubled for keepers and singles for formatting:

  • fr'\w{{{count},}}'
  • r'\w{{{},}}'.format(count)

Post back if you need more help. Good luck!!!