Regular Expressions 101

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"
(?P<type>RESERVED)(?:::)(?P<desc>[\w#()/]*)
"
gm
Named Capture Group type
(?P<type>RESERVED)
RESERVED
matches the characters RESERVED literally (case sensitive)
Non-capturing group
(?:::)
::
matches the characters :: literally (case sensitive)
Named Capture Group desc
(?P<desc>[\w#()/]*)
Match a single character present in the list below
[\w#()/]
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
\w matches any word character (equivalent to [a-zA-Z0-9_])
#()/
matches a single character in the list #()/ (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