Regular Expressions 101

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"
\b(\w{6})\b
"
\b assert position at a word boundary: (^\w|\w$|\W\w|\w\W)
1st Capturing Group
(\w{6})
\w
matches any word character (equivalent to [a-zA-Z0-9_])
{6} matches the previous token exactly 6 times
\b assert position at a word boundary: (^\w|\w$|\W\w|\w\W)
Your regular expression does not match the subject string.

Regular Expression
No Match

r"
"

Test String