private static Saml2NameIdentifier ProcessNameIdentifier(Claim claim)
        {
            var saml2NameIdentifier = new Saml2NameIdentifier(claim.Value);

            claim.ExtractProperty(ClaimProperties.SamlNameIdentifierFormat,
                value => saml2NameIdentifier.Format = new Uri(value));
            claim.ExtractProperty(ClaimProperties.SamlNameIdentifierNameQualifier,
                value => saml2NameIdentifier.NameQualifier = value);
            claim.ExtractProperty(ClaimProperties.SamlNameIdentifierSPNameQualifier,
                value => saml2NameIdentifier.SPNameQualifier = value);
            claim.ExtractProperty(ClaimProperties.SamlNameIdentifierSPProvidedId,
                value => saml2NameIdentifier.SPProvidedId = value);

            return saml2NameIdentifier;
        }