Python 正则表达式验证URN

1. Check whether a string consists entirely of a valid URN
Match:
(?x)\Zurn:
# Namespace Identifier
[a-zA-Z0-9][a-zA-Z0-9-]{0,31}:
# Namespace Speficic String
[a-zA-Z0-9()+,\-.:=@;$_!*'%/?#]+
\Z

Result:
urn:nihao:nihao

2. Find a URN in a larger body of text
Match:
(?x)\burn:
# Namespace Identifier
[a-zA-Z0-9][a-zA-Z0-9-]{0,31}:
# Namespace Speficic String
[a-zA-Z0-9()+,\-.:=@;$_!*'%/?#]+

Result:
urn:nihao:nihao urn:nihao:good

3. Find a URN in a larger body of text, assuming that punctuation at the end of the URN
if part of the (English) text in which the URN is quoted rather than part of the URN itself
(?x)\burn:
# Namespace Identifier
[a-zA-Z0-9][a-zA-Z0-9-]{0,31}:
# Namespace Speficic String
[a-zA-Z0-9()+,\-.:=@;$_!*'%/?#]*[a-zA-Z0-9+=@$/]