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Python Regular Expressions in Python Introduction to Regular Expressions Negated Numbers

1 Answer

Chris Freeman
Chris Freeman
Treehouse Moderator 68,029 Points

The challenge is looking for anything that isn't a 7, 8, or 9. You can find any set of characters using square brackets. Putting a caret (^) as the first member of the character set negates the match:

re.findall(r'[1-3]', string)  # find any 1, 2, or 3
re.findall(r'[^1-3]', string)  # find anything that *isn't* a 1, 2, or 3

Post back if you need more help. Good luck.