Regular Expressions 101

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"
(.*(!)$)|([^a-z])+(\?)*$
"
1st Alternative
(.*(!)$)
1st Capturing Group
(.*(!)$)
.
matches any character (except for line terminators)
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
2nd Capturing Group
(!)
! matches the character ! with index 3310 (2116 or 418) literally (case sensitive)
$ asserts position at the end of the string, or before the line terminator right at the end of the string (if any)
2nd Alternative
([^a-z])+(\?)*$
3rd Capturing Group
([^a-z])+
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
Match a single character not present in the list below
[^a-z]
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
4th Capturing Group
(\?)*
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
\? matches the character ? with index 6310 (3F16 or 778) literally (case sensitive)
$ asserts position at the end of the string, or before the line terminator right at the end of the string (if any)
Your regular expression does not match the subject string.

Regular Expression
No Match

r"
"

Test String