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\s+a Unicode whitespace character, repeated at least once
Group att_name(?P<att_name>[^\s]+) Negated Character Class[^\s]+ +matches at least one character outside the set below:
\sa Unicode whitespace character
\s+a Unicode whitespace character, repeated at least once
Group att_value(?P<att_value>[^\s{]+|"[^"]+?") Negated Character Class[^\s{]+ +matches at least one character outside the set below:
\sa Unicode whitespace character
{the literal { (12310 / 1738 / 7B16)
"the literal " (3410 / 428 / 2216)
Negated Character Class[^"]+? +?matches at least one character outside the set below:
"the literal " (3410 / 428 / 2216)
"the literal " (3410 / 428 / 2216)
\s?optionally matches a Unicode whitespace character
Group att_body(?P<att_body>{[\s\S]+?})? ?repeats the group contents below at most once:
{the literal { (12310 / 1738 / 7B16)
+?matches at least one character from the set below:
\sa Unicode whitespace character
\Sany character that is not Unicode whitespace
}the literal } (12510 / 1758 / 7D16)