current validator for iri and iri-reference requires package rfc3987.
package rfc3987 is licensed under GPLv3+

For legal reasons, I cannot use GPL-licensed dependencies, so I am using the installation extra "format-nongpl".
This very extra does not bring any validation for iri and iri-reference, as far as I understand.

I would like to add capabilities for iri and iri-reference validation when using the "format-nongpl" extra.
Candidates for non-GPL libraries:

• https://pypi.org/project/rfc3987-syntax/
• https://pypi.org/project/iriuri/

What do you think? Which candidate would you prefer?