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The Predicate type is defined in the urn:mace:shibboleth:2.0:afp namespace, the schema for which can be located at http://shibboleth.net/schema/idp/shibboleth-afp.xsd
The deprecated basicdeprecated basic:Predicate type is defined in the urn:mace:shibboleth:2.0:afp:mf:basic namespace, the schema for which can be located at http://shibboleth.net/schema/idp/shibboleth-afp-mf-basic.xsd
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