Regular Expressions 101

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"
("[^"]*")* (^|[^a-zA-Z"]) (?P<var>A) ($|[^a-zA-Z0-9"])
"
gxs
All the errors detected are listed below, from left to right, as they appear in the pattern.
" An unescaped delimiter must be escaped with a backslash (\)
" An unescaped delimiter must be escaped with a backslash (\)
" An unescaped delimiter must be escaped with a backslash (\)
" An unescaped delimiter must be escaped with a backslash (\)
" An unescaped delimiter must be escaped with a backslash (\)
Your regular expression does not match the subject string.

Regular Expression
No Match

r"
"
gxs

Test String