Regular Expressions 101

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"
^(..[^^].{4,22}\$|[^?]+\w)$|2
"
gm
1st Alternative
^(..[^^].{4,22}\$|[^?]+\w)$
^ asserts position at start of a line
1st Capturing Group
(..[^^].{4,22}\$|[^?]+\w)
1st Alternative
..[^^].{4,22}\$
. matches any character (except for line terminators)
. matches any character (except for line terminators)
Match a single character not present in the list below
[^^]
^ matches the character ^ with index 9410 (5E16 or 1368) literally (case sensitive)
.
matches any character (except for line terminators)
{4,22} matches the previous token between 4 and 22 times, as many times as possible, giving back as needed (greedy)
\$ matches the character $ with index 3610 (2416 or 448) literally (case sensitive)
2nd Alternative
[^?]+\w
Match a single character not present in the list below
[^?]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
? matches the character ? with index 6310 (3F16 or 778) literally (case sensitive)
\w matches any word character (equivalent to [a-zA-Z0-9_])
$ asserts position at the end of a line
2nd Alternative
2
2 matches the character 2 with index 5010 (3216 or 628) literally (case sensitive)
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.

Regular Expression
No Match

r"
"
gm

Test String