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Start your free trialSahar Nasiri
7,454 PointsCan we use "?" as a optional character
All the characters in the [] could exist or not, can't we write the print line like this:
print(re.findall(r'[-?\w?\d?+?.?]@[-?\w?\d?.?]', data))
1 Answer
Chris Freeman
Treehouse Moderator 68,426 PointsSquare brackets []
define a character class (or set). Repeating letters within the brackets are redundant. Putting the question mark inside the class makes it also an optional character of the class. Without a question mark outside the class (and no other +
, *
or ?
modifier) means exactly one character of the class.
So your proposed pattern would only find a single character followed by a @
followed by another single character.