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  1. import re
  2. print( [x.group() for x in re.finditer(r'([a-zA-Z])(?!\1)(?i:\1)', 'aADFfGcCgs')] )
  3. print( [x for x,y in re.findall(r'(([a-zA-Z])(?!\2)(?i:\2))', 'aADFfGcCgs')] )
Success #stdin #stdout 0.02s 9664KB
comments (?)
stdin 
Standard input is empty
stdout 
['aA', 'Ff', 'cC']
['aA', 'Ff', 'cC']
https://ideone.com/tKb2To
language:
Python 3 (python  3.9.5)
created:
4 years ago
visibility:
secret

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