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Writing a regex expression that finds 'zz' in a word but not at the start and the end

December 4, 2021

I am having some difficulty writing a regex expression that finds words in a text that contain ‘zz’, but not at the start and the end of the text. These are two of my many attempts:

pattern = re.compile(r'(?!(?:z){2})[a-z]*zz[a-z]*(?!(?:z){2})')
pattern = re.compile(r'\b[^z\s\d_]{2}[a-z]*zz[a-y][a-z]*(?!(?:zz))\b')

Thanks

>Solution :

Well, the direct translation would be

\b(?!zz)(?:(?!zz\b)\w)+zz(?:(?!zz\b)\w)+\b

See a demo on regex101.com.

Programmatically, you could use

text = "lorem ipsum buzz mezzo mix zztop but this is all"

words = [word 
         for word in text.split()
         if not (word.startswith("zz") or word.endswith("zz")) and "zz" in word]

print(words)

Which yields