Regular Expressions 101

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"
^[a-z]+[0-9/\(\)G]+\s+.+\n
"
gmi
^ asserts position at start of a line
Match a single character present in the list below
[a-z]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
a-z matches a single character in the range between a (index 97) and z (index 122) (case insensitive)
Match a single character present in the list below
[0-9/\(\)G]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case insensitive)
/ matches the character / with index 4710 (2F16 or 578) literally (case insensitive)
\( matches the character ( with index 4010 (2816 or 508) literally (case insensitive)
\) matches the character ) with index 4110 (2916 or 518) literally (case insensitive)
G matches the character G with index 7110 (4716 or 1078) literally (case insensitive)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v  ])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
.
matches any character (except for line terminators)
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\n matches a line-feed (newline) character (ASCII 10)
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)
i modifier: insensitive. Case insensitive match (ignores case of [a-zA-Z])
Your regular expression does not match the subject string.

Regular Expression
No Match

r"
"
gmi

Test String